_Delphinapterus._[156]—This genus is closely allied to the last in

external form, as well as anatomical structure, differing mainly in

the very distinct character of the dentition. Teeth from ⁸⁄₈ to ¹⁰⁄₁₀,

occupying the anterior three-fourths of the rostrum and corresponding

portion of the mandible, rather small, conical, and pointed when unworn,

but usually becoming obliquely truncated, separated by intervals

considerably wider than the diameter of the tooth, and implanted

obliquely, the crowns inclining forwards, especially in the upper jaw.

Skull rather narrow and elongated, depressed. Premaxillæ convex in front

of the nares. Rostrum about equal in length to the cranial portion of the

skull, triangular, broad at the base, and gradually contracting towards

the apex, where it is somewhat curved downwards. Vertebræ: C 7, D 11,

L 9, C 23; total 50. Cervical vertebræ free. Manus broad, short, and

rounded, all the digits being tolerably well developed, except the first.

No dorsal fin, but a low ridge in its place.

[Illustration: FIG. 91.—Beluga or White Whale (_Delphinapterus leucas_).

From a specimen taken in the river St. Lawrence, and exhibited in London,

1877.]

One existing species, _D. leucas_ (Fig. 91), the Beluga or White Whale,

so called from its pure white colour, about 12 feet long, abundant in

the Arctic seas, and extending as far south on the American coast as the

river St. Lawrence, which it ascends for a considerable distance. On rare

occasions it has been seen on the coast of Scotland.

Remains of a Cetacean from the Lower Pliocene of Tuscany have been

referred by Brandt to this genus under the name _D. brocchii_.

In all the remaining genera of _Delphinidæ_ the cervical region of the

vertebral column is very short, and the first two, and usually more, of

the vertebræ are firmly united.

_Phocæna._[157]—Teeth ²⁵⁄₂₅, small, occupying nearly the whole length

of the rostrum, with compressed, spade-shaped crowns, separated from

the root by a constricted neck (Fig. 92). Rostrum rather shorter than

the cranium proper, broad at the base and tapering towards the apex.

Premaxillæ raised into tuberosities in front of the nares. The frontal

bones forming a somewhat square, elevated protuberance in the middle line

of the skull behind the nares, rising altogether above the flattened

nasals. Pterygoids very small, and widely separated in the middle line.

Symphysis of mandible very short. Vertebræ: C 7, D 13, L 14, C 31; total

65 (subject to slight individual variations). First to sixth cervical

vertebræ, and sometimes the seventh also, coalesced. Manus of moderate

size, oval, slightly falcate; second and third digits nearly equal in

length; fourth and fifth well developed, but shorter. Dorsal fin near the

middle of the back, triangular; its height considerably less than the

length of the base; its anterior edge frequently furnished with one or

more rows of conical horny tubercles.

[Illustration: FIG. 92.—Teeth of Porpoise. Twice natural size.]

The common Porpoise (Fig. 93), _P. communis_, is the best known of

British Cetaceans. The word Porpoise (sometimes spelled Porpus and

Porpesse) is apparently derived from the French _porc_ and _poisson_, or

the Italian _porco_ and _pesce_, and thus corresponds with some of the

English vernacular appellations, “hog-fish,” “sea-hog,” “herring-hog,”

and the German _Meerschwein_, whence the usual modern French name of the

animal, _marsouin_. “Porpoise” is commonly used by sailors to designate

all the smaller Cetaceans, especially those numerous species which

naturalists call “Dolphins”; but in scientific language it is restricted

to the genus _Phocæna_ of Cuvier, of which the Porpoise of the British

seas, _Phocæna communis_, Cuvier (_Delphinus phocæna_, Linnæus), is the

type.

The Common Porpoise, when full grown, attains a length of 5 feet or a

little more. The dimensions of an adult female specimen from the English

Channel were as follows:—length in straight line from nose to median

notch between the flukes of the tail, 62½ inches; from the nose to the

anterior edge of the dorsal fin, 29 inches; height of dorsal fin, 4½

inches; length of base of dorsal fin, 8 inches; length of pectoral fin,

9¼ inches; breadth of pectoral fin, 3½ inches; breadth of tail flukes,

13 inches. The under jaw projects about half an inch beyond the upper

one. The aperture of the mouth is tolerably wide, and is bounded by

stiff immobile lips, and curves slightly upwards at the hinder end. The

eye is small, and the external ear represented by a minute aperture in

the skin, scarcely larger than would be made by the puncture of a pin,

situated about 2 inches behind the eye. The pectoral fins are of moderate

size, and slightly falcate. The upper parts are dark gray, or nearly

black, according to the light in which they are viewed, and the state

of moisture or otherwise of the skin; the under parts are pure white.

The line of demarcation between these colours is not distinct (washes or

splashes of gray encroaching upon the white on the sides), and varies

somewhat in different individuals. Usually it passes from the throat

(the anterior part of which, with the whole of the under jaw, is dark)

above the origin of the pectoral fin, along the middle of the flank, and

descends again to the middle line before reaching the tail. Both sides of

the pectoral and caudal fins are black.

[Illustration: FIG. 93.—The Common Porpoise (_Phocæna communis_).]

The Porpoise is sociable and gregarious in its habits, being usually

seen in small herds, and frequenting coasts, bays, and estuaries rather

than the open ocean. It is the commonest Cetacean in the seas around the

British Isles, and not unfrequently ascends the river Thames, having been

seen as high up as Richmond; it has also been observed in the Seine at

Neuilly, near Paris. It frequents the Scandinavian coasts, entering the

Baltic in the summer; and is found as far north as Baffin’s Bay, and as

far west as the coasts of the United States. Southward its range is more

limited than that of the Common Dolphin, as, though very common on the

Atlantic coasts of France, it rarely enters the Mediterranean.

It feeds on fish, such as mackerel, pilchards, and herrings, of which

it devours large quantities, and, following the shoals, is often caught

by fishermen in the nets along with its prey. In former times it was a

common and esteemed article of food in England and in France, but is

now rarely if ever eaten, being commercially valuable when caught only

for the oil obtained from its blubber. Its skin is sometimes used for

leather and boot-thongs, but the so-called “porpoise hides” are generally

obtained from the Beluga.

A closely similar if not identical species from the American coast of the

North Pacific has been described under the name of _Phocæna vomerina_,

and another from the mouth of the Rio de la Plata as _P. spinipennis_.

[Illustration: FIG. 94.—Diagrammatic section of the stomach of the

Porpoise. _a_, Œsophagus; _b_, left, or cardiac, compartment; _c_, middle

compartment; _d_ and _e_, the two divisions of the right, or pyloric,

compartment; _f_, pylorus; _g_, duodenum, dilated at its commencement;

_h_, biliary duct.]

The stomach of the Porpoise (Fig. 94) may be taken as a typical

example of this organ in the Cetacea. The first and by far the largest

compartment (_b_) may be regarded as a kind of crop, or dilatation of

the large œsophagus (_a_). It is lined by a thick white epithelium,

which ceases abruptly at the entrance into the next cavity. It

corresponds to the cardiac compartment of the stomach in the Ungulates

and certain Rodents; but, although its walls do not appear to contain

peptic glands, its contents undergo partial digestion—probably caused

by the regurgitation into it of the secretions of the second, or true

digestive compartment (_c_). This, which is much smaller than the first,

has very thick walls, the mucous membrane being filled with numerous

tubular glands. The surface of this membrane is smooth and soft, being

thrown into numerous folds, which in this genus are arranged in a very

peculiar and characteristic manner, so as to form a series of prominent

longitudinal ridges, each of which sends off short lateral ridges at

right angles to itself, which interdigitate with those proceeding from

the next longitudinal ridge. The remainder of the stomach (_d_ to _f_)

may be compared to the pyloric antrum of the stomach of ordinary mammals.

It is elongated, cylindrical, and intestiniform, with a smooth lining

membrane, sharply bent upon itself, and terminating in a very small

circular pyloric aperture (_f_). In the Porpoise the commencement of

this cavity is constricted off from the remainder, so as to form a small

globular sac. In most Dolphins (as _Tursiops_, _Globicephalus_, and

_Grampus_) there are two such small sacs of very similar size and form,

communicating by circular pylorus-like apertures; and in _Hyperoödon_ the

whole compartment is divided by a series of constrictions into as many as

seven separate cavities, which have been regarded as distinct stomachs.

Immediately beyond the pylorus the duodenum has a globular dilatation, as

in the camels and some other Ungulates, into the lower end of which the

biliary duct (_h_) enters.

An allied species, differing mainly in the absence of dorsal fin, and

in the teeth (with the same form of crown) being fewer in number and of

larger size, called _Delphinus phacænoides_ by Cuvier, _D. melas_ by

Schlegel, forms the type of Gray’s genus _Neomeris_.[158] It is rather

smaller than the Common Porpoise, and almost entirely black in colour.

Common off the coast of Bombay, it has been met with in other parts of

the Indian Ocean, and near Japan. The British Museum recently received

a specimen taken in the Chinese river Yang-tse-kiang nearly a thousand

miles from the sea, which only differs from others from India in wanting

a patch of small horny tubercles on the back. As such tubercles are

present or absent in otherwise similar individuals of _P. communis_,

it is doubtful whether they can be regarded as constituting a specific

character.

_Cephalorhynchus._[159]—Rostrum as long and sometimes slightly longer

than the cranial portion of the skull. Pterygoids widely separated from

one another. Teeth small (less than 3 mm. in diameter), ²⁵⁄₂₅ to ³⁰⁄₃₀.

Vertebræ: C 7, D 13, L 15, C 30; total 65. Dorsal fin low, obtusely

triangular or rounded. Pectoral fins rather small, narrow, and ovate.

Typified by _C. heavisidei_, from the southern seas. _C. eutropia_ is

a very distinct form from the same seas, known only by the skull, and

referred provisionally to this genus.

_Orcella._[160]—Teeth ¹²⁄₁₂ to ¹⁴⁄₁₄, small, conical, pointed, rather

closely set, and occupying nearly the whole length of the rostrum. Skull

subglobular, high. Rostrum nearly equal in length to the cranial portion

of the skull, tapering. Pterygoids widely separated from one another.

Manus of moderate size, not elongated, but somewhat pointed. All the

bones of the digits broader than long, except the proximal phalanges of

the index and third fingers. Dorsal fin rather small, placed behind the

middle of the body. Two species, both of small size—_O. brevirostris_,

from the Bay of Bengal, and _O. fluminalis_, from the Irawadi river, from

300 to 900 miles from the sea. Our present knowledge of the anatomy,

geographical distribution, and habits of these interesting Cetaceans is

almost entirely due to the researches of Dr. J. Anderson.[161]

_Orca._[162]—Teeth about ¹²⁄₁₂, occupying nearly the whole length of the

rostrum, very large and stout, with conical recurved crowns, and large

roots, expanded laterally and flattened, or rather hollowed, on the

anterior and posterior surfaces. Rostrum about equal in length to the

cranial part of the skull, broad and flattened above, rounded in front;

premaxillæ broad and rather concave in front of the nares, contracted

at the middle of the rostrum, and expanding again towards the apex.

Pterygoids of normal form, but not quite meeting in the middle line.

Vertebræ: C 7, D 11-12, L 10, C 23; total 51 or 52. Bodies of the first

and second and sometimes the third cervical vertebræ united; the rest

free. Pectoral fin very large, ovate, nearly as broad as long. All the

phalanges and metacarpals broader than long. General form of body robust.

Dorsal fin near the middle of the back, very high and pointed. Anterior

part of the head broad and depressed.

The animals composing this genus are met with in almost all seas from

Greenland to Tasmania, but the number of species is still uncertain,

and possibly they may be all reduced to one. They are readily known,

when swimming in the water, by the high, erect, falcate dorsal fin,

whence their common German name of _Schwertfisch_ (Sword-fish). By

English sailors they are generally known as “Grampuses” or “Killers.”

They are distinguished from all their allies by their great strength and

ferocity, being the only Cetaceans which habitually prey on warm-blooded

animals, for, though fish form part of their food, they also attack

and devour Seals, and various species of their own order, not only the

smaller Porpoises and Dolphins, but even full-sized Whales, which last

they combine in packs to hunt down and destroy, as Wolves do the larger

Ruminants.

[Illustration: FIG. 95.—The Killer Whale, or Grampus (_Orca gladiator_).

From Hunter.]

_Orca citoniensis_, of the Italian Pliocene, was of smaller size than

the existing Killer. Teeth and periotic bones from the Suffolk Crag not

improbably belong to the same species.

_Pseudorca._[163]—Teeth about ¹⁰⁄₁₀. Cranial and dental characters

generally like those of _Orca_, except that the roots of the teeth are

cylindrical. Vertebræ: C 7, D 10, L 9, C 24; total 50. First to sixth

or seventh cervical vertebræ united. Bodies of the lumbar vertebræ

distinguished from those of the preceding genera by being more elongated,

the length being to the width as 3 to 2. Pectoral fin of moderate size,

narrow, and pointed. Dorsal fin situated near the middle of the back,

of moderate size, falcate. Head in front of the blowhole high, and

compressed anteriorly, the snout truncated.

This genus was first known by the discovery of a skull in a subfossil

state in a fen in Lincolnshire, named by Sir R. Owen _Phocæna

crassidens_. Animals of apparently the same species were afterwards

met with in small herds on the Danish coast, and fully described by

Reinhardt. Others subsequently received from Tasmania were supposed

at first to indicate a different species, but comparison of a larger

series of specimens from these extremely distant localities fails to

establish any characteristic difference, and indicates an immense range

of distribution for a species apparently so rare. The length of this

Cetacean is about 14 feet, and its colour entirely black.

_Globicephalus._[164]—Teeth ⁸⁻¹²⁄₈₋₁₂, confined to the anterior half

of the rostrum and corresponding part of the mandible, small, conical,

curved, sharp-pointed when unworn, sometimes deciduous in old age. Skull

broad and depressed. Rostrum and cranial portion about equal in length.

Upper surface of rostrum broad and flat. Premaxillæ strongly concave

in front of the nares, as wide at the middle of the rostrum as at the

base, or wider, and very nearly or completely concealing the maxillæ in

the anterior half of this region. Pterygoids of normal form, meeting,

or very nearly so, in the middle line. Vertebræ: C 7, D 11, L 12-14,

C 28-29; total 58 or 59. Bodies of the anterior five or six cervical

vertebræ united. Length of the bodies of the lumbar and anterior caudal

vertebræ about equal to their width. Pectoral limb very long and narrow,

the second digit the longest, and having as many as 12 or 13 phalanges,

the third shorter (with 9 phalanges), the first, fourth, and fifth very

short. Fore part of the head very round, in consequence of the great

development of a cushion of fat, placed on the rostrum of the skull in

front of the blowhole. Dorsal fin low and triangular, the length of its

base considerably exceeding its vertical height.

The type of this well-marked genus is _G. melas_, the Pilot Whale, Ca’ing

Whale, or Grindhval of the Faroe islanders, which attains the length of

20 feet, and is of nearly uniform black colour, except the middle of the

under surface, which is lighter. These animals are extremely gregarious,

and, unlike the Killers, are mild and inoffensive in disposition, feeding

principally on cephalopods. Their eminently sociable character constantly

leads to their destruction, since when attacked they instinctively rush

together and blindly follow the leaders of the herd. When they are seen

in the neighbourhood of land, the fishermen endeavour to get to seaward

of them in their boats, and with shouting and firing of guns to drive

them into a bay or fjord, pursuing them until they run themselves on

shore in their alarm. In this way many hundreds at a time are frequently

driven ashore and killed, when a herd enters one of the bays or fjords of

the Faroe Islands or north of Scotland. Animals of this well-marked genus

are found in nearly all seas, and their specific distinctions are not yet

made out. Specimens from the Australian coasts, where they are generally

called “Black-fish,” are quite indistinguishable, either by external or

osteological characters, from those of the North Atlantic.

[Illustration: FIG. 96.—The left periotic bone of _Globicephalus

uncidens_; from the Suffolk Crag. Natural size. The grooved surface on

the right is the anterior facet for articulation with the tympanic; the

posterior tympanic articulation being on the opposite side of the figure.

(From the _Cat. Foss. Mamm. Brit. Mus._ pt. v.)]

Teeth, periotic (Fig. 96) and tympanic bones from the Suffolk Crag,

described as _G. uncidens_, indicate a form apparently closely allied to

the existing species. The periotic is figured in order to illustrate the

distinctive characters of that bone in the _Delphinidæ_.

_Grampus._[165]—Teeth none in the upper jaw; in the mandible few (3 to

7 on each side), and confined to the region of the symphysis. Vertebræ:

C 7, D 12, L 19, C 30; total 68. General external characters much as in

_Globicephalus_, but the fore part of the head less rounded, and the

pectoral fin less elongated.

But one species, _G. griseus_, is certainly known, about 13 feet long,

and remarkable for its great variability of colour. It has been found,

though rarely, in the North Atlantic and Mediterranean. A skull from the

Cape of Good Hope, which differs slightly from that of the above, has

been described under the name of _G. richardsoni_.

_Feresia._[166]—This genus, known at present only by two skulls, may be

provisionally placed here. These appear to indicate a form connecting

_Globicephalus_, _Grampus_, and _Lagenorhynchus_. From the latter they

differ chiefly in the smaller number (about ¹²⁄₁₂) and much larger size

(6-7 mm. in diameter at base of crown) of the teeth.

_Lagenorhynchus._[167]—Rostrum scarcely exceeding the length of the

cranium, broad at the base and gradually tapering towards the apex,

depressed. Pterygoids normal, meeting in the middle line. Teeth small

(not exceeding 4 mm. in diameter), ²³⁄₂₃ to ³³⁄₃₃. Vertebræ very

numerous, 80 to 90. Spines and transverse processes of the lumbar

vertebræ very long and slender; centra short. Externally, head with a

short but not very distinct beak. Two species, _L. albirostris_ and _L.

acutus_, are occasionally captured on the British coasts. Other species

occur elsewhere.

_Group B._—Head with distinctly elongated rostrum, or beak, generally

marked off from the prenarial adipose elevation by a V-shaped groove.

Rostrum of skull considerably longer than the cranial portion. Atlas and

axis firmly united; all the other cervical vertebræ free.

If we add to it the above-mentioned genus, _Lagenorhynchus_, this group

will include all the true Dolphins, Bottle-noses, or, as they are more

commonly called by seafaring people, “Porpoises,” which are found in

considerable abundance in all seas, some species being habitually

inhabitants of large rivers, as the Amazon. They are all among the

smaller members of the order, none exceeding 10 feet in length. Their

food is chiefly fish, for the capture of which their long narrow

beaks, armed with numerous sharp-pointed teeth, are well adapted, but

some appear also to devour crustaceans and molluscs. They are mostly

gregarious, and the agility and grace of their movements in the water

are constant themes of admiration to the spectators of the scene when a

“school of Porpoises” is observed playing round the bows of a vessel at

sea.

_Delphinus._[168]—Teeth very numerous in both jaws, ⁴⁰⁄₄₀ to ⁶⁰⁄₆₀,

occupying nearly the whole length of the rostrum, small, close-set,

conical, pointed, slightly curved. Rostrum elongated, usually about

double the length of the cranial portion of the skull. Pterygoids of

normal form, meeting in the middle line throughout their length. Palate

with deep lateral grooves. Vertebræ 73 to 75. Pectoral fin of moderate

size, narrow, pointed, somewhat falcate. Second and third digits well

developed; the rest rudimental.

The type of the genus is the Common Dolphin of the Mediterranean (_D.

delphis_, Fig. 97), also found in the Atlantic, and of which a closely

allied if not identical form is met with in the Australian seas (_D.

forsteri_) and in the North Pacific (_D. bairdi_). Other species are _D.

janira_, _D. major_, etc.

[Illustration: FIG. 97.—The Common Dolphin (_Delphinus delphis_). From

Reinhardt.]

_Tursiops._[169]—Rostrum tapering moderately from base to apex; palate

not grooved; symphysis of mandible short; other cranial characters as in

_Delphinus_. Teeth ²¹⁄₂₁ to ²⁵⁄₂₅, stout (6 to 7 mm. in antero-posterior

diameter). Vertebræ: C 7, D 13, L 17, C 27; total 64. Limbs as in

_Delphinus_. Represented by the widely distributed _T. tursio_; _T.

catalania_ being a second form. Fossil remains of this genus from the

Italian Pliocene have been recently described.

_Prodelphinus._[170]—Rostrum somewhat variable; mandibular symphysis

short (less than one-fifth the length of the ramus); other cranial

characters as in the preceding genus. Teeth ³⁰⁄₃₀ to ⁵⁰⁄₅₀, small, not

exceeding 3 mm. in diameter. Vertebræ 73 to 78. Limbs as in _Delphinus_.

Four leading types of this genus are recognised (all of which have

numerous synonyms) viz. _P. obscurus_, _P. euphrosyne_, _P. doris_, and

_P. longirostris_.

Péron’s Dolphin (_Delphinus leucorhamphus_, Péron, or _Leucorhamphus

peroni_, Lilljeborg) resembles some forms of _Prodelphinus_ in its

cranial characters; but having no dorsal fin, it has been separated

generically by some writers. It is not improbable that _Delphinus

borealis_, Peale, from the North Pacific, in which there is likewise no

dorsal fin, may be an allied form.

_Steno._[171]—Rostrum long, narrow, and compressed, very distinct from

the cranium; mandibular symphysis as long as, or longer than one-fourth

the length of the ramus; other cranial characters as in the preceding

genus. Teeth ²¹⁄₂₁ to ²⁵⁄₂₅, of comparatively large size (5-6 mm. in

diameter); surface of their crowns finely grooved. Vertebræ: C 7, D 12, L

15, C 32; total 66. Represented by _S. rostratus_, from which the forms

which have received other names are probably not specifically separable.

_Sotalia._[172]—Pterygoids narrow, not meeting in the middle line, and

in their inner borders diverging posteriorly, instead of being parallel

as in the preceding genera; other cranial characters much as in _Steno_.

Teeth tolerably large (4-5 mm. in diameter), ³⁰⁄₃₀ to ³⁵⁄₃₅, with smooth

enamelled surface. Vertebræ: C 7, D 12, L 10-14, C 22; total 51-55.

Pectoral fin broad at base, the breadth being caused by the considerable

development and position of the two outer digits. Six species are

provisionally recognised as distinct, including the Chinese White Dolphin

(_S. sinensis_) and _S. pallidus_ from the river Amazon.

_Bibliography of Cetacea._—D. F. Eschricht, _Untersuchungen

über die Nordischen Wallthiere_, 1849, contains a copious

bibliography of the group up to the date of publication.

Since that time numerous monographs on special families and

genera have been published, and a large illustrated general

work, _Ostéographie des Cétacés_, by P. J. Van Beneden and P.

Gervais, 1869-80. Besides those already referred to in the

footnotes, the following may be mentioned; viz. J. F. Brandt,

“Untersuchungen über die Fossilen und Subfossilen Cetaceen

Europa’s,” in _Mém. de l’Acad. Imp. de St. Pétersbourg_, 7ⁱᵉᵐᵉ

sér. vol. xx. 1873; C. M. Scammon, _Marine Mammals of the N. W.

Coast of North America_, 1874; W. H. Flower, “On the characters

and Divisions of the Families of the _Delphinidæ_,” _Proc.

Zool. Soc._ 1883, p. 466, and _List of the Specimens of Cetacea

in the British Museum_, 1885; F. W. True, “Review of the Family

Delphinidæ,” _Bull. U.S. Nat. Museum_, No. 36, 1889; P. J. Van

Beneden, _Histoire Naturelle des Cétacés des Mers d’Europe_,

1889.

For fossil forms, in addition to the works of Van Beneden,

Gervais, and Brandt, already cited, the reader may refer to

various memoirs published by the former writer in the _Bull.

Ac. R. Belgique_ and _Ann. Mus. R. Hist. Nat. Belg._ See also

R. Lydekker, “The Cetacea of the Suffolk Crag,” _Quart. Journ.

Geol. Soc._ vol. xlii. p. 7 (1887), and _Catalogue of the

Fossil Mammalia in the British Museum_, pt. v. (1887).

CHAPTER IX

THE ORDER UNGULATA

Under this term may be included provisionally a large and rather

heterogeneous group of mammals, the existing members of which form

the Pecora and Belluæ of Linnæus, the Ruminantia and Pachydermata of

Cuvier. A few years ago it was found convenient to restrict the order

to a well-marked and distinctly circumscribed group, comprising the two

sections known as Perissodactyla and Artiodactyla, and to leave out

such isolated forms as the Elephant and Hyrax; but the discovery of a

vast number of extinct species, which could not be brought under the

definition of either perissodactyle or artiodactyle Ungulates, and yet

are evidently allied to both, and to a certain extent bridge over the

interval between these and the isolated groups just mentioned, makes it

necessary either to introduce a number of new and ill-defined ordinal

divisions, or to widen the scope of the original order so as to embrace

them all.

The existing forms are all animals eminently adapted for a terrestrial

life, and in the main for a vegetable diet. Though a few are more or

less omnivorous, and may under some circumstances kill living creatures

smaller and weaker than themselves for food, none are distinctly

and habitually predaceous. Their teeth are markedly heterodont and

diphyodont,—the milk set being well developed and not completely changed

until the animal attains its full stature. The molars have broad crowns

with tuberculated or ridged surfaces. There are no clavicles.[173] Their

toes are provided with blunt, broad nails, or in the majority of cases

with hoofs, more or less enclosing the ungual phalanges. The scaphoid

and lunar bones of the carpus are always distinct. The humerus has no

entepicondylar foramen. The number of digits varies from five to one; and

the radius and ulna may be united together.

The more generalised of the fossil forms do not conform in all

respects to the above-mentioned characters; clavicles being present in

_Typotherium_, and perhaps in some of the Condylarthra, while in the

latter group the humerus may have an entepicondylar foramen, and thus

approximate to the corresponding bone of the Carnivora. Wide as is the

gap between existing Carnivores and Ungulates, there are indeed more or

less strongly marked evidences of affinity between the earlier members of

the two orders, as will be again noticed under the head of the suborder

Condylarthra. A departure from the normal type of foot-structure is

exhibited by the extinct _Macrotherium_, provisionally included in the

Perissodactyla, where the digits terminated in long and curved claws.

As a general rule, the cheek-teeth have distinct roots, and in those of

the existing suborders a gradual increase in the height of the crowns

of these teeth may be noticed in passing from the more generalised

to the more specialised types. Those teeth in which the crowns are

low, and their whole structure visible from the grinding surface, are

termed _brachydont_ (Fig. 122); while those with higher crowns, in

which the bases of the infoldings of enamel are invisible from the

grinding surface, are known as _hypsodont_ (Fig. 123). Again, when the

tubercles on the crowns of the molars are more or less cone-like in form

the tooth is said to be _bunodont_; but when they are expanded in an

antero-posterior direction and curved into a crescent shape the tooth is

described as _selenodont_.

[Illustration: FIG. 98.—Right fore foot of Indian Elephant. × ⅛. U, ulna;

R, radius; _c_, cuneiform; _l_, lunar; _sc_, scaphoid; _u_, unciform;

_m_, magnum; _td_, trapezoid; _tm_, trapezium; I to V, first to fifth

digit.]

The whole order may be divided into the Ungulata Vera, containing the

suborders Perissodactyla and Artiodactyla, and a somewhat heterogeneous

assemblage of animals which may be called Subungulata or Ungulata

Polydactyla. Cope has pointed out a character in the structure of the

carpus by which the latter are differentiated from the former. Thus in

all the Subungulata the bones of the proximal and distal row retain the

primitive or more typical relation to each other (see Fig. 98); the os

magnum of the second row articulating mainly with the lunar of the

first, or with the cuneiform, but not with the scaphoid. But in the group

to which the vast majority of modern Ungulates belong the second or

distal row has been shifted altogether towards the inner side of the limb

(see Fig. 99), so that the magnum is brought considerably into relation

with the scaphoid, and is entirely removed from the cuneiform, as in the

great majority of existing mammals.

It will be on the whole more convenient to commence our survey of the

members of this suborder with the more specialised group of the Ungulata

Vera, in which the Artiodactyla will be taken first.

UNGULATA VERA.[174]

In the typical Ungulata the feet are never plantigrade, and the

functional toes do not exceed four—the inner digit being suppressed,

at all events in all forms which have existed since the Upper Eocene

period.[175] The os magnum of the carpus articulates freely with the

scaphoid. The allantois is largely developed, and the placenta, so far

as is known, is non-deciduate; the chorionic villi being either evenly

diffused or collected in groups or cotyledons (in Pecora). The testes

descend into a scrotum. There is never an os penis. The uterus is

bicornuate. The mammæ are usually few and inguinal, or may be numerous

and abdominal (as in Suina), but are never solely pectoral. The cerebral

hemispheres in existing Ungulates are well convoluted.

The group is now, and has been throughout almost the whole of the

Tertiary period, composed of two perfectly distinct sections, differing

from each other, not only in the obvious characters of the structure

of the limbs, but in so many other parts of their organisation that

they must be considered as of the rank at least of suborders. The

characters of these divisions, first indicated by Cuvier, were thoroughly

established by Owen, by whom the names whereby they are now generally

known were proposed.

_Suborder_ ARTIODACTYLA.

This is a well-defined group, traceable from the Eocene period, though

then apparently by no means so numerous as the Perissodactyles. Some of

its types, as that represented in the existing Swine, have retained to

the present time much of the primitive character of the group; but others

have been gradually becoming more specialised and perfected in structure,

and its latest modification, the Cavicorn Ruminants or _Bovidæ_

(Antelopes, Sheep, and Oxen), are now the dominating members of the great

Ungulate order, widespread in geographical range, rich in generic and

specific variation, and numerous in individuals—forming in all these

respects a great contrast to such decadent types as those represented by

the Tapirs and Rhinoceroses.

[Illustration: FIG. 99.—Bones of right fore foot of existing

Artiodactyles. A, Pig (_Sus scrofa_), × ⅓; B, Red Deer (_Cervus

elaphus_), × ⅐; C, Camel (_Camelus bactrianus_), × ⅛. _U_, Ulna; _R_,

radius; _c_, cuneiform; _l_, lunar; _s_, scaphoid; _u_, unciform; _m_,

magnum; _td_, trapezoid; _tm_, trapezium. From Flower’s _Osteology of

Mammalia_.]

The principal anatomical characters by which the Artiodactyles are

distinguished from the Perissodactyles are as follows. The premolar and

molar teeth usually not alike, the former being single and the latter

two-lobed. The last lower molar of both first and second dentition

almost invariably three-lobed; and the first tooth of the upper cheek

series always without a milk-predecessor. Nasal bones not expanded

posteriorly. No alisphenoid canal. Dorsal and lumbar vertebræ together

always nineteen, though the former may vary from twelve to fifteen. Femur

without third trochanter. Third and fourth digits of both feet almost

equally developed, and their ungual phalanges flattened on their inner or

contiguous surfaces, so that each is not symmetrical in itself, but when

the two are placed together they form a figure symmetrically disposed to

a line drawn between them. Or, in other words, the axis or median line

of the whole foot is a line drawn between the third and fourth digits,

while in the Perissodactyles it is a line drawn down the centre of the

third digit. Distal articular surface of the astragalus divided into two

nearly equal facets, one for the navicular and the other for the cuboid

bone. The calcaneum with an articular facet for the lower end of the

fibula. Stomach almost always more or less complex. Colon convoluted.

Cæcum small. Placenta diffused or cotyledonary. Mammæ few and inguinal,

or numerous and abdominal.

In treating of many sections of mammals, it is only from the existing

species that our characters and classification can be derived, and to

these chiefly our observations upon the group must be directed, many of

the extinct forms being so little known that they can only be referred

to incidentally. With the Ungulata, however, it is quite otherwise. The

history of the Artiodactyla throughout the Tertiary period is now well

known, and throws great light upon the position and relations of the

existing groups.

The principal modifications which have taken place in the type from

its earliest known and most generalised manifestation have been the

following:—

1. As regards the teeth. Assumption by the grinding surfaces of the molar

teeth either of a bunodont or of a selenodont form. Modification of the

latter from a brachydont to a hypsodont type. Loss of upper incisors.

Development of canines into projecting tusks. Loss of anterior premolars.

2. As regards the limbs. Reduction of the ulna from a complete and

distinct bone to a comparatively rudimentary state, in which it coalesces

more or less firmly with the radius. Reduction of the fibula till nothing

but its lower extremity remains. Reduction and final loss of external

pair of digits (second and fifth), with coalescence of the metapodial

bones of the two middle digits. Union of the navicular and cuboid, and

sometimes the ectocuneiform, bones of the tarsus.

3. Change of form of the odontoid process of the axis vertebra from a

cone to a hollow half-cylinder.

4. Development of horns or antlers on the frontal bones, and gradual

complication of form of antlers.

5. By inference only, increasing complication of stomach with ruminating

function superadded. Modification of placenta from simple diffused to

cotyledonary form.

The primitive Artiodactyles, with the typical number (44) of incisor,

canine, and molar teeth, brachydont molars, conical odontoid process,

four distinct toes on each foot, with metapodium and all carpal bones

distinct, no frontal appendages, and (in all probability) simple stomach

and diffused placenta, were separated at a very early period into

Bunodonts and Selenodonts, although there is evidence of intermediate

forms showing a complete transition from the one modification to

the other. These and other fossil forms so completely connect the

four groups—Suina, Tylopoda, Tragulina, and Pecora—into which the

existing members of the suborder have become divided, that in a general

classification embracing both living and extinct forms these divisions

cannot be maintained. In the present work, however, it will be convenient

to retain them, mention being made of some of the chief annectant forms

in separate sections.

SUINA.

The existing members of this group are characterised by their bunodont

molars, and the absence of a complete fusion of the third and fourth

metapodials to form a “cannon-bone.” The full Eutherian dentition is very

frequently present.

Remains of very generalised swine-like animals have been abundantly

found in Tertiary formations both in America and Europe. In the former

continent they never (so far as present evidence indicates) underwent any

great diversity of modification, but gradually dwindled away and almost

died out, being only represented in the actual fauna by the two closely

allied species of Peccary, among the smallest and most insignificant

members of the group, which have existed almost unchanged since the

Miocene age at least, if the evidence of teeth alone can be trusted. In

the Old World, on the other hand, the swine have played a more important

part in recent times, having become widely distributed, and throwing

off some curiously specialised forms. At the present time, though not

very numerous in species, they range through the greater part of the Old

World, except within or near the Arctic Circle, although, in common with

all the other members of the great Ungulate order, they were completely

absent from the whole of the Australian region, until introduced by man

in very recent times.

The existing swine-like animals may be divided naturally into three

families:—I. _Hippopotamidæ_; II. _Suidæ_, or true Pigs; III.

_Dicotylidæ_, or Peccaries.[176]

_Family_ HIPPOPOTAMIDÆ.

[Illustration: FIG. 100.—Grinding surface of a worn molar of

_Hippopotamus amphibius_. (From Owen.)]

Muzzle very broad and rounded. Feet short and broad, having four

subequal toes, with short rounded hoofs, all reaching the ground in

walking. Incisors not rooted, but continuously growing; those of the

upper jaw curved and directed downwards; those of the lower straight and

procumbent. Canines very large, curved, continuously growing; those of

the upper jaw directed downwards. Stomach complex. No cæcum.

_Hippopotamus._[177]—This genus may be taken to include all the known

members of the family; it appears to have been always confined to the

Old World. The dentition may be expressed by the formula _i_ ²⁻³⁄₁₋₃,

_c_ ¹⁄₁, _p_ ⁴⁄₄, _m_ ³⁄₃. The crowns of the molars (Fig. 100) when worn

present trefoil-shaped surfaces of dentine; and those of the premolars

are sharp. The facial portion of the skull is much elongated, the orbits

are tubular and very prominent, and the mandible has a large rounded

descending flange at its angle. The ears are small, the tail is short,

and the legs are likewise so short that the belly is raised but a little

distance above the ground. The brain is not richly convoluted, and

differs very considerably from that of the Pigs, approximating in some

respects to that of the Camel and Giraffe, but on the whole standing

very much by itself. The stomach of the common species is of enormous

dimensions, having an axial length of 11 feet, and measuring upwards

of 15 feet along the greater curvature. Its axis is longitudinal, the

pylorus being situated almost in the pelvis, and it is divided into three

distinct compartments, of which the third is cylindrical. The liver of

the adult is of extremely simple form, elongated transversely, and narrow

from above downwards. With the exception of a few tufts of hair on the

lips, on the sides of the head and neck, and at the extremity of the

short compressed tail, the skin of the hippopotamus, some portions of

which are two inches in thickness, is entirely destitute of covering.

[Illustration: FIG. 101.—The Hippopotamus (_Hippopotamus amphibius_).]

The common Hippopotamus (_H. amphibius_), widely distributed in the

rivers and lakes of the African continent, is a huge bulky animal,

characterised by having only two incisors on either side of each jaw; the

central lower pair being very much larger than the outer ones. A male

from the Upper Nile which lived for nearly thirty years in the gardens of

the Zoological Society of London measured 12 feet along the back from the

nose to the root of the tail.

The Hippopotamus lives in herds of from twenty to forty individuals on

the banks and in the beds of rivers, in the neighbourhood of which it

finds its food. This consists chiefly of grass and aquatic plants, of

which it consumes enormous quantities, the stomach being capable of

containing from 5 to 6 bushels. These animals feed principally by night,

remaining in the water during the day, although in districts where

they are undisturbed by man they are less exclusively aquatic. In such

regions they put their heads boldly out of the water to blow, but when

rendered suspicious by persecution, they become exceedingly cautious,

only exposing their eyes and nostrils above the water, and even this they

prefer doing amid the shelter of water plants. In spite of their enormous

size and uncouth form, they are expert swimmers and divers, and can

remain under the water from five to eight minutes. They are said to walk

with considerable rapidity on the bottoms of rivers, beneath at least a

foot of water. At nightfall they come on land to feed; and when, as often

happens on the banks of the Nile, they reach cultivated ground, they do

immense damage to growing crops, destroying by their ponderous tread even

more than they devour.

A much smaller species, known as the Pigmy Hippopotamus (_H.

liberiensis_), inhabits some of the rivers of Western Africa, and is

characterised by having only a single pair of lower incisors. Mainly on

this account, it has been proposed to regard this species as representing

a distinct genus, under the name of _Chœropsis_; but since it agrees

so essentially in other characters with the common form, and sometimes

has two incisors on one side of the lower jaw, it appears preferable

to include it in the type genus. The greater relative size of the

brain-cavity as compared with the facial portion of the skull renders,

indeed, the contour of the skull decidedly different from that of _H.

amphibius_, but this is a feature generally found in young individuals of

larger species, and also in the adults of allied smaller forms.

Both the existing species are now exclusively confined to Africa, but

in the Pleistocene and Pliocene periods the genus was widely spread

over the Old World. Thus in the Upper Pliocene of the Continent and

the Pleistocene of England we meet with remains of a very large

fossil Hippopotamus which cannot be specifically distinguished from

_H. amphibius_. In the Pleistocene and Pliocene of India there are

two species having three pairs of incisors in both jaws. Of these _H.

palæindicus_ has the second pair in the lower jaw very minute, and

evidently just about to disappear; from which we learn that it is this

pair which is missing in _H. amphibius_. In the still more generalised

_H. sivalensis_ the three incisors in the lower jaw are of equal size.

Hexaprotodont species also occur in the Upper Tertiaries of Burma and

Algeria. Small tetraprotodont species (_H. pentlandi_ and _H. minutus_)

have left their remains in enormous quantities in the caves and fissures

of Sicily and Malta.

_Family_ SUIDÆ.

An elongated mobile snout, with an expanded, truncated, nearly naked,

flat, oval terminal surface in which the nostrils are placed. Feet

narrow; four completely developed toes on each. Hoofs of the two middle

toes with their contiguous surfaces flattened. The outer (second and

fifth) digits of existing forms not reaching to the ground in the

ordinary walking position. Teeth variable in number, owing to the

suppression in some forms of an upper incisor and one or more premolars.

Incisors rooted. Upper canines curving more or less outwards or upwards.

Stomach simple, except for a more or less developed pouch near the

cardiac orifice. A cæcum. Colon spirally coiled. Confined to the Old

World.

The mandible has no descending flange at the angle. The crowns of the

molars do not wear into such distinct trefoils as in the Hippopotamus,

and are oblong in shape. The last molar of both the upper and lower jaw

(Fig. 102) has an additional hinder lobe or talon, varying in size in the

different species. The upper premolars are simpler than the true molars.

[Illustration: FIG. 102.—Grinding surface of a worn third right lower

molar of the Wild Boar (_Sus scrofa_). After Owen.]

_Sus._[178]—Dentition: _i_ ³⁄₃, _c_ ¹⁄₁, _p_ ⁴⁄₄, _m_ ³⁄₃; total 44.

Upper incisors diminishing rapidly in size from the first to the third.

Lower incisors long, narrow, closely approximated, and almost horizontal

in position, their apices inclining towards the middle line; the second

slightly larger than the first, the third much smaller. Canines strongly

developed and with persistent roots and partial enamel-covering, those

of the upper jaw not having the usual downward direction, but curving

strongly outwards, upwards, and finally inwards, while those of the lower

jaw are directed upwards and outwards with a gentle backward curve,

their hinder edges working and wearing against the front edges of the

upper canines[179]. They appear externally to the mouth as tusks, the

form of the upper lip being modified to allow of their protrusion, but

are much less developed in the females than in the males. The teeth of

the molar series gradually increase in size and complexity from first

to last, and are arranged in contiguous series, except that the first

lower premolar is separated by an interval from the second. First and

second upper premolars with compressed crowns and two roots. The third

and fourth have an inner lobe developed on the crown, and an additional

pair of roots. The first and second true molars have quadrate crowns,

with four principal obtuse conical cusps, around which numerous accessory

cusps are clustered. The length of the third molar is nearly equal

(antero-posteriorly) to that of the first and second together, its crown

having, in addition to the four principal cusps, a large posterior talon

or heel, composed of numerous clustered conical cusps, and supported by

several additional roots. The lower molar teeth resemble generally those

of the upper jaw, but are narrower. Milk dentition: _i_ ³⁄₃, _c_ ¹⁄₁,

_m_ ³⁄₃; total 28,—the first permanent premolar having no predecessor in

this series. The third incisor, in both upper and lower jaws, is large,

developed before the others, and has much the size, form, and direction

of the canine. Vertebræ: C 7, D 13-14, L 6, S 4, C 20-24. The hairy

covering of the body varies much under different conditions of climate,

but when best developed, as in the European Wild Boar, consists of long

stiff bristles, mostly abundant on the back and sides, and of a close

softer curling undercoat.

The skull of the Pigs (Figs. 103-105) has the axis of the face bent down

upon the basicranial axis, as is also the case with the Sheep. Its most

striking feature is the elevation and backward slope of the occipital

crest formed by the union of the supraoccipital and parietals. The broad

and flat frontals have small postorbital processes, which do not join the

zygomata, so that the orbits are open behind. The nasals are very long

and narrow; and the premaxillæ send up long nasal processes, stopping

short of the frontals. A peculiar prenasal bone is developed at the

anterior extremity of the mesethmoid, which serves to strengthen the

cartilaginous snout. The palate is long and narrow, and extends behind

the last molar tooth. In most species the occipital crest is more nearly

vertical than in the skull represented in Fig. 104.

[Illustration: FIG. 103.—Left lateral view of the dentition of the Boar

(_Sus scrofa_), the roots of the teeth being exposed by removing the

external lamina of bone.]

[Illustration: FIG. 104.—Left lateral view of the skull of _Sus

longirostris_. ⅕ natural size. (From Nehring.)]

[Illustration: FIG. 105.—Frontal aspect of the cranium of _Sus

longirostris_, ⅕ natural size. (From Nehring.)]

This genus occurs at present under three principal modifications or

subgenera.

_A._—_Sus_ proper comprises a number of animals found in a wild state

throughout the greater part of Europe (except where exterminated by

human agency), the north of Africa, southern continental Asia, and

the great islands of the Malayan archipelago, Formosa, and Japan. The

following among others have been admitted by many zoologists as distinct

species:—_Sus scrofa_, the Wild Boar of Europe, Asia Minor, and North

Africa, once common throughout the British Isles; _S. sennaarensis_,

North-East Africa; _S. cristatus_, India; _S. vittatus_, Java, Borneo,

Amboyna, Batchian; _S. papuensis_, New Guinea; _S. timorensis_, Timor

and Rotti; _S. andamanensis_, Andaman Islands; _S. taëvanus_, Formosa;

_S. leucomystax_, Japan; _S. verrucosus_, Java, Borneo, Ceram; _S.

barbatus_, Borneo; _S. celebensis_, Celebes, Philippines, and Moluccas;

_S. longirostris_, Borneo and Java. The last four species form an

allied group in which the facial portion of the skull may be greatly

elongated; _S. barbatus_, and _S. celebensis_ being characterised by

the small size and simple structure of the talon of the third molars.

The skull of _S. longirostris_ is shown in Figs. 104 and 105. The small

_S. andamanensis_ also has very simple third molars. _S. vittatus_, _S.

leucomystax_, _S. cristatus_, _S. taëvanus_, and _S. papuensis_ form

another group, in which the third molar is generally of very complex

structure, more or less closely allied to the Wild Boar; and Dr. Nehring

is inclined to think that the whole five might be included under a

single specific name. This list will give some idea of the geographical

distribution of wild Pigs, but it must be borne in mind that through

the whole of this region, and in fact now throughout the greater part

of the habitable world, Pigs are kept by man in a domesticated state,

and it is still an open question whether some of the wild Pigs of the

islands named above may not be local races derived originally from, or

crossed with, imported domestic specimens. In New Zealand a wild or

rather “feral” race is already established, the origin of which is of

course quite recent, since it is well ascertained that no animal of the

kind ever lived upon the island until after its settlement by Europeans.

Whether the various breeds of domestic Pigs have been derived from

one or several sources is still unknown. As in so many similar cases,

there is no historic evidence upon the subject, and the researches of

naturalists, as Nathusius, Rütimeyer, Rolleston, Nehring, and others, who

have endeavoured to settle the question on anatomical evidence, have not

led to any satisfactory conclusions. It is, however, tolerably certain

that all the species or forms of wild Pigs enumerated above and all the

domestic races are closely allied, and it is probable (though of this

there has been no opportunity of proof) will breed freely together.

It is a curious circumstance that the young of all the wild kinds of

Pigs (so far as yet is known) present a uniform coloration, being dark

brown with longitudinal stripes of a paler colour, a character which

completely disappears after the first few months. On the other hand,

this peculiar marking is rarely seen in domestic Pigs in any part of

the world, although it has been occasionally observed. It is stated by

Darwin that the Pigs which have run wild in Jamaica and the semiferal

Pigs of New Granada have resumed this aboriginal character, and produce

longitudinally striped young; these must of course be the descendants

of domestic animals introduced from Europe since the Spanish conquest,

as before that time there were no true Pigs in the New World. Another

character by which the European domestic Pig differs from any of the wild

species is the concave outline of the frontal region of the skull, a form

still retained by the feral Pigs in New Zealand.

_B._—The diminutive Pig of the Nipal, Terai, and Bhutan, _Sus salvanius_,

has been separated from the rest by Hodgson under the generic name of

_Porcula_, but all the alleged distinctive characters prove on more

careful investigation to have little real value. Owing to its retired

habits and power of concealment under bushes and long grass in the depths

of the great Sal Forest, which is its principal home, very little has

been known of this curious little animal, scarcely larger than a hare.

The acquisition of living specimens in the London Zoological Gardens has,

however, afforded opportunities for careful anatomical observation.[180]

[Illustration: FIG. 106.—Wild Boar and Young.]

_C._—Two well-marked species of African Swine have been with more reason

separated under the name of _Potamochœrus_. The dentition differs

from that of the true _Sus_, inasmuch as the anterior premolars have

a tendency to disappear; sometimes in adult specimens the first upper

premolar is retained, but it is usually absent, as well as the first

and often the second lower premolars. The molar teeth are also less

complex: the last especially having a much less developed talon. There

are likewise characteristic cranial differences. The two species are very

distinct in outward appearance and coloration. One is _S. africanus_,

the South African River-Hog, or Bosch-Vark, of a gray colour, and the

other _S. porcus_, the West African Red River-Hog (Fig. 107), remarkable

for its vivid colouring and long pencilled ears. It should be noted that

the young of both these species, as well as of the pigmy _S. salvanius_,

present the striped character of the true _Sus_, a strong indication of

close affinities, whereas in all the following forms this is absent.

[Illustration: FIG. 107.—The Red River-Hog (_Sus porcus_). From Sclater,

_Guide to Animals in Zoological Society’s Gardens_, 1883, p. 183.]

The genus _Sus_, in the above extended sense, is well represented in

the Tertiaries of the Old World from the period of the Lower Pliocene

upwards. In the Pliocene and Pleistocene of India _S. falconeri_ and

_S. karnuliensis_ are characterised by the extremely complex structure

of the molars, in which they show decided signs of approximation to

the Wart-Hogs; the same feature being exhibited by _S. phacochœroides_

of the Algerian Pliocene. _S. titan_ and _S. giganteus_, of the Indian

Pliocene, together with _S. antiquus_ and _S. erymanthius_, of the

corresponding European deposits, are very large species characterised by

their comparatively simple molars; _S. titan_ being fully as large as a

Tapir. _S. hysudricus_ of the Pliocene of India, and _S. palæochœrus_

of that of Europe, are smaller allied species not improbably related

to _S. andamanensis_, with which they agree in molar structure. _S.

arvernensis_, of the Upper Pliocene of France, appears to be allied to

_S. africanus_; while in the diminutive _S. punjabiensis_ of the Pliocene

of North-Western India we probably have the direct ancestor of _S.

salvanius_.

[Illustration: FIG. 108.—Head of Babirusa (_Babirusa alfurus_).]

_Babirusa._[181]—Dentition: _i_ ²⁄₃, _c_ ¹⁄₁, _p_ ²⁄₂, _m_ ³⁄₃; total 34.

The total number of teeth is therefore considerably reduced, the outer

upper incisor and the two anterior premolars of both jaws being absent.

The molars, especially the last, are smaller and simpler than in _Sus_;

but the great peculiarity of this genus is the extraordinary development

of the canines of the male. These teeth (Fig. 108) are ever-growing,

long, slender, and curved, and entirely without enamel covering. Those of

the upper jaw are directed upwards from their base, so that they never

enter the mouth, but piercing the skin of the face, resemble horns rather

than teeth, and curve backwards, downwards, and finally often forwards

again, almost or quite touching the skin of the forehead. Vertebra:

C 7, D 13, L 16, S 4. There is but one species (_B. alfurus_), found

only in the islands of Celebes and Buru. Its external surface is almost

entirely devoid of hair. With regard to the curiously modified dentition,

Wallace (_Malay Archipelago_, vol. i. p. 435) makes the following

observations:—“It is difficult to understand what can be the use of these

horn-like teeth. Some of the old writers supposed that they served as

hooks by which the creature could rest its head on a branch. But the

way in which they usually diverge just over and in front of the eye has

suggested the more probable idea, that they serve to guard these organs

from thorns and spines while hunting for fallen fruits among the tangled

thickets of rattans and other spiny plants. Even this, however, is not

satisfactory, for the female, who must seek her food in the same way,

does not possess them. I should be inclined to believe rather that these

tusks were once useful, and were then worn down as fast as they grew, but

that changed conditions of life have rendered them unnecessary, and they

now develop into a monstrous form, just as the incisors of the Beaver and

Rabbit will go on growing if the opposite teeth do not wear them away. In

old animals they reach an enormous size, and are generally broken off as

if by fighting.”

_Phacochœrus._[182]—The Wart-Hogs, so called from the large cutaneous

lobes projecting from each side of the face, have the teeth still more

remarkably modified than in _Babirusa_. The milk-dentition, and even

the early condition of the permanent dentition, is formed on the same

general type as that of _Sus_, except that certain of the typical teeth

are absent, the formula being _i_ ¹⁄₃, _c_ ¹⁄₁, _p_ ³⁄₂, _m_ ³⁄₃, total

34; but as age advances all the teeth have a tendency to disappear,

except the canines and the posterior molars, which in some cases are the

only teeth left in the jaws, and attain an extraordinary development.

The upper canines especially are of great size, and curve outwards,

forwards, and upwards. Their enamel covering is confined to the apex, and

soon wears away. The lower canines are much more slender, but follow the

same curve: except on the posterior surface, their crowns are covered

with enamel. Unlike those of the Babirusa, the canines of the Wart-Hog

are large in both sexes. The third molar tooth of both jaws is of great

size, and presents a structure at first sight unlike that of any other

mammal, being composed of numerous (22-25) parallel cylinders or columns,

each with pulp-cavity, dentine, and enamel covering, and packed together

with cement. Careful examination will, however, show that a similar

modification to that which has transformed the comparatively simple molar

tooth of the Mastodon into the extremely complex grinder of the Indian

Elephant has served to change the tooth of the common Pig into that of

_Phacochœrus_, and, as already mentioned, some of the fossil Indian and

African species of _Sus_ indicate the mode in which this transition came

about. The tubercles which cluster over the surface of the crown of the

molars of the common Pig are elongated and drawn out into columns in the

Wart-Hog, as the low transverse ridges of the Mastodon’s tooth become the

leaf-like plates of the Elephant’s.

Two species of this genus are commonly but rather doubtfully

distinguished:—_P. africanus_, Ælian’s Wart-Hog, widely distributed

over the continent; and _P. æthiopicus_, Pallas’s Wart-Hog, confined to

South-Eastern Africa. In specimens attributed to the latter species the

dentition reaches its most complete reduction, as in adult animals the

upper incisors are absent and the lower ones worn down to the roots.

_Family_ DICOTYLIDÆ.

Snout as in _Suidæ_. Dentition: _i_ ²⁄₃, _c_ ¹⁄₁, _p_ ³⁄₃, _m_ ³⁄₃; total

38. Incisors rooted; upper canines directed downwards, with sharp cutting

hinder edges. Toes, four on the fore feet and three on the hind feet (the

fifth wanting). Stomach complex. A cæcum. Confined to the New World.

_Dicotyles._[183]—The teeth of the Peccaries (_Dicotyles_) differ from

those of the true Pigs (_Sus_) numerically in wanting the upper outer

incisor and the anterior premolar on either side of each jaw, and also

in the circumstance that the last premolar is nearly as complex as the

molars. The upper canines have their points directed downwards, not

outwards or upwards as in the Boars, and are very sharp, with cutting

hinder edges, and completely covered with enamel until worn. The lower

canines are large, directed upwards and outwards, and slightly curved

backwards. The premolar and molar teeth form a continuous series,

gradually increasing in size from the first to the last. The true molars

have square quadricuspidate crowns. The stomach is much more complex

than in the true Pigs, almost approaching that of the ruminants. In

the feet the two middle (third and fourth) metapodial bones, which are

completely separate in the Pigs, are united at their upper ends, as

in the ruminants. On the fore foot the two (second and fifth) outer

toes are equally developed as in Pigs, but on the hind foot, although

the inner (or second) is present, the outer (or fifth) toe is entirely

wanting, giving an unsymmetrical appearance of the member, very unusual

in Artiodactyles. Vertebræ: C 7, D 14, L 5, S 4, C 7. As in the Pigs,

the snout is truncated, and the nostrils are situated in its flat,

expanded, disc-like termination. The ears are rather small, ovate, and

erect; and there is no external appearance of a tail. The surface of

the body is well covered with thick bristly hair, and rather behind

the middle of the back is a large and peculiar gland, which secretes an

oleaginous substance with a powerful musky odour. This was mistaken by

the old travellers for a second navel, a popular error which suggested to

Cuvier the name of _Dicotyles_. When the animal is killed for food, it

is necessary speedily to remove this gland, otherwise it will taint the

whole flesh so as to render it uneatable.

[Illustration: FIG. 109.—The Collared Peccary (_Dicotyles tajacu_).]

There are two species,[184] so nearly allied that they will breed

together freely in captivity. Unlike the true Pigs, they never appear

to produce more than two young ones at a birth. The Collared Peccary

(_D. tajacu_, Linn., _torquatus_, Cuvier), Fig. 109, ranges from the

Red River of Arkansas through the forest districts of Central and South

America as far as the Rio Negro of Patagonia. Generally it is found

singly or in pairs, or at most in small herds of from eight to ten,

and is a comparatively harmless creature, not being inclined to attack

other animals or human beings. Its colour is dark gray, with a white

or whitish band passing across the chest from shoulder to shoulder.

The length of the head and body is about 36 inches. The White-lipped

Peccary or Warree (_D. labiatus_, Cuvier) is rather larger, being about

40 inches in length, of a blackish colour, with the lips and lower jaw

white. Its range is less extensive, since it is not found farther north

than British Honduras or south of Paraguay. It is generally met with in

large herds of from fifty to a hundred or more individuals, and is of

a more pugnacious disposition than the former species, and capable of

inflicting severe wounds with its sharp tusks. A hunter who encounters

a herd of them in a forest has often to climb a tree as his only chance

of safety. Both species are omnivorous, living on roots, fallen fruits,

worms, and carrion; and when they approach the neighbourhood of villages

and cultivated lands they often inflict great devastation upon the crops

of the inhabitants.

Remains of the two existing species of Peccary, as well as of one

much larger extinct form, are found in the cavern-deposits of Brazil;

while large Peccaries also occur in the Pleistocene of the United

States, which, although they have been referred to a distinct genus,

_Platygonus_, on account of their relatively smaller incisors and

somewhat simpler premolars, may well be included in _Dicotyles_.

[Illustration: FIG. 110.—The three left upper molars of _Hyotherium

perimense_, from the Pliocene of India.]

_Allied Extinct Genera._—In the Tertiary deposits of both the Old and

New World occur remains of Pig-like animals which, so far as we can

judge, appear to connect the Peccaries so closely with the true Pigs

as to render the _Dicotylidæ_ really inseparable from the _Suidæ_.

Of these the American genus _Chænohyus_ has the lower canine with a

triangular cross section and received into a notch in the upper jaw,

as in the Peccaries, but the fourth upper premolar is simpler than the

molars, as in the under-mentioned genus _Hyotherium_. The typical forms

have only three premolars, but in others, which it has been proposed

to separate generically as _Bothriolabis_, there are four of these

teeth. _Hyotherium_, of the Pliocene and Miocene of the Old World, is

a generalised form allied both to _Sus_ and _Dicotyles_ as well as to

certain extinct genera. The upper molars (Fig. 110) are characterised

by their square crowns, the last having no distinct third lobe, and

coming into use before the first is much worn, while the last premolar

is simpler than the true molars. The canines, which have an oval section

and are scarcely larger than the incisors, are not received into a notch

in the upper jaw. In the Pliocene of India there occurs an apparently

allied genus known as _Hippohyus_, in which the crowns of the molars

are much taller, and have lateral infoldings of the enamel, producing

a very complex pattern on the worn crowns. The European Miocene genus

_Listriodon_, with the dental formula _i_ ³⁄₃, _c_ ¹⁄₁, _p_ ³⁄₃, _m_

³⁄₃, differs from all the preceding in having the anterior and posterior

pairs of tubercles of the molars united into ridges running across their

crowns, so that these teeth resemble the lower molars of the Tapir. The

genus is also found in the Lower Pliocene of India.

EXTINCT TRANSITIONAL ARTIODACTYLES.

In this place it will be convenient to notice briefly a few of the

extinct types of Tertiary Artiodactyles which connect the existing

bunodont Suina with the more specialised selenodont groups mentioned

below so closely as to show that in a strictly palæontological

classification such groups cannot be maintained. It should be mentioned

that while some of these extinct forms were in all probability actual

ancestral links between the bunodonts and selenodonts, others, like

the Anoplotheres, died out entirely without giving rise to any more

specialised descendants.

[Illustration: FIG. 111.—The imperfect third left upper molar of

_Hyopotamus giganteus_, Miocene, India. (From the _Palæontologia

Indica_.)]

_Chœropotamidæ._—In this family the molars are intermediate in

structure between those of the _Suidæ_ and the next family. The upper

ones have very broad crowns, with the five columns arranged as in

_Anthracotherium_; while the premolars are not secant, and may be

very large. The best known forms are the small _Cebochœrus_ of the

Phosphorites of Central France; _Chœropotamus_ of the Upper Eocene, the

type species of which was of the size of a large Pig, with the dental

formula _i_ ³⁄₃, _c_ ¹⁄₁, _p_ ⁴⁄₃, _m_ ³⁄₃, and no distinctly selenodont

structure in the molars; the much larger _Elotherium_, from the Upper

Eocene and Lower Miocene of both the Old and New Worlds, which presents

the very rare feature of the absence of a third lobe to the last lower

molar; and the equally large _Tetraconodon_ of the Pliocene of India,

in which this third lobe was present and the premolars were of enormous

size. The remarkable North American Eocene genus _Achænodon_ should

perhaps also be placed here.

[Illustration: FIG. 112.—A right upper molar of _Merycopotamus pusillus_,

Pliocene, India. (From the _Palæontologia Indica_.)]

_Anthracotheriidæ._—The genera _Anthracotherium_ and _Hyopotamus_, of

the upper Eocene and Miocene, have the typical Eutherian dental formula;

the upper molars (Fig. 111) carrying three columns on the anterior and

two on the posterior half of the crown, all of which are of a more or

less decidedly selenodont structure. The mandible has a descending

flange at the angle. The figured tooth (in which the antero-internal and

antero-median columns are imperfect) may be compared with the diagram

given in Fig. 5, p. 32, when the homology of the columns or tubercles

will be at once apparent, the broken antero-median column representing

the protoconule. Some of the species are of large size, while others are

comparatively small.

_Merycopotamus._—The genus _Merycopotamus_ of the lower Pliocene

of India may be regarded as an Anthracotheroid which has lost the

antero-median column to the upper molars (Fig. 112), so that these teeth

are consequently quadrituberculate; and may thus be regarded as typical

examples of the brachy-selenodont modification of molar structure.

_Cotylopidæ._—The Miocene genus _Cotylops_ (_Oreodon_[185]) is the type

of a large American family in which the upper molars are selenodont and

usually have four columns, while the lower canine is approximated to

the incisors and its form and function assumed by the first premolar.

The last upper premolar is simpler than the molars. There is no flange

to the angle of the mandible; and the feet have four digits. The

affinities of this peculiar family are probably widely spread, but they

may have been derived from the _Anthracotheriidæ_. The type genus has

the full Eutherian dentition, but in some of the more specialised forms

(_Cyclopidius_) the upper incisors may be wanting, and large vacuities

occur in the lachrymal region. The generalised genus _Protoreodon_, of

the Upper or Uinta Eocene, has five cusps on the upper molars, arranged

as in the _Anthracotheriidæ_. The pollex is retained in the manus of the

type genus.

[Illustration: FIG. 113.—Restoration of _Anoplotherium commune_ (Upper

Eocene). Cuvier.]

The family may be divided into subfamilies as follows:—

I. Upper molars with four columns.

1. Orbits open, no lachrymal fossa, a diastema, the last

upper premolar with two outer columns, outer wall of

upper molars concave and inclined inwards.—_Agriochœrinæ_

(_Agriochœrus_).

2. Orbits closed, a lachrymal fossa, no diastema, the last

upper premolar with one outer column; outer wall of upper

molars flattened.—_Cotylopinæ_ (_Cotylops_, _Eporeodon_,

_Merycochœrus_, _Cyclopidius_, etc.)

II. Upper molars with five columns.—_Protoreontinæ_ (_Protoreodon_).

_Anoplotheriidæ._—This family includes several Upper Eocene European

genera, with selenodont upper molars, carrying five columns arranged as

those in _Anthracotherium_. One of the earliest known, _Anoplotherium_,

was fully described by Cuvier from remains found in the Paris gypsum-beds

(Upper Eocene). Its forty-four teeth formed a series unbroken by a gap

or diastema, and were of uniform height (as in Man alone of existing

mammals). Its tail was long, with large chevron bones underneath, not

usually found in Ungulates, and there were either three or two toes on

each foot. It was in many respects a much-specialised form, apparently

not on the line of descent of any of the existing groups.

_Dacrytherium_ is an allied genus whose dentition leads on to that of the

smaller _Xiphodon_. The latter genus is characterised by the compressed

and elongated form of the crowns of the first three premolars, which thus

approximate to those of the Chevrotains. There were only two functional

digits to the feet. The so-called _Hyopotamus picteti_, of the Swiss

Eocene, is a species of _Dacrytherium_.

_Cænotheriidæ._—The typical representatives of this family are small

animals not larger than the Chevrotains, with the full complement of

teeth, generally no marked gap in the series, and the crowns of the upper

molars carrying two columns on the anterior and three on the posterior

half of the crown—precisely the reverse of the arrangement obtaining in

the _Anthracotheriidæ_. The known forms are from the Upper Eocene and

Lower Miocene of Europe. In _Cænotherium_ the molars are selenodont,

while they are bunodont in _Dichobunus_. _Homacodon_, of the Bridger

Eocene of the United States, is closely allied to the latter. The first

lower premolar of _Dichobunus_ assumes the form and function of a canine.

_Spaniotherium_ (_Metriotherium_) is a much larger form, in which the

molars are not unlike those of _Anthracotherium_, if the arrangement of

the cusps were reversed; it occurs in the Eocene Phosphorites of France.

It is suggested that the _Tylopoda_ may have originated from this group.

_Tapirulus_ is a small Eocene Artiodactyle with the columns of the upper

molars, which are somewhat like those of _Hyopotamus_, tending to form

transverse ridges; its family position is uncertain.

_Dichodontidæ._—The European genera included in this family all have

quadritubercular selenodont molars, and show signs of approximating

more or less closely to existing types. _Dichodon_, from the Upper

Eocene and Lower Miocene, has the full complement of teeth, which show

no diastema, and have low crowns. The fourth upper premolar has four

columns, like the true molars, and the corresponding lower tooth three

complete lobes; these features being unknown in any other Selenodonts.

In _Lophiomeryx_, of the same beds, the somewhat higher crowns of the

molars approximate to those of the _Cervidæ_, but the hinder lobes of

the upper ones are imperfectly developed; the genus may be allied,

to the _Tragulidæ_. In the small _Gelocus_, of the Lower Miocene,

the molars are not unlike those of _Dichodon_; but the navicular and

cuboid bones of the tarsus were fused together, and the metatarsals had

united to form a “cannon-bone,” although the metacarpals still remained

distinct. It is not improbable that upper incisors were wanting; and it

has been suggested that we have in this genus the ancestral type of the

_Tragulidæ_ and _Cervidæ_.

TYLOPODA.

_Family_ CAMELIDÆ.

This group is represented at the present day by the two species of

Camels of the Old World and the Llamas of South America, collectively

constituting the family _Camelidæ_. The special characters which

the Llamas and Camels have in common, and the combination of which

distinguishes them from the rest of the Artiodactyles, are as follows.

The premaxillæ have the full number of incisor teeth in the young state,

and the outermost is persistent through life as an isolated laniariform

tooth. The canines are present in both jaws, and those of the mandible

are differentiated from the long, procumbent, and spatulate incisors,

being suberect and pointed. The crowns of the true molars belong to the

crescentic or selenodont type, and are very hypsodont; but one or more

of the anterior premolars is usually detached from the series, and is of

simple pointed form. The auditory bulla is filled with cancellous tissue.

The hinder part of the body is much contracted, and the femur long and

vertically placed, so that the knee-joint is lower in position, and the

thigh altogether more detached from the abdomen than in most quadrupedal

mammals. The limbs are long, but with only the third and fourth digits

developed; no traces of any of the others being present. The trapezoid

and magnum of the carpus, and the cuboid and navicular of the tarsus

are distinct. The two metapodial bones of each limb are confluent for

the greater part of their length, though separated for a considerable

distance at the lower end. Their distal articular surfaces, instead of

being pulley-like, with deep ridges and grooves, as in other recent

Artiodactyles, are simple, rounded, and smooth. The proximal phalanges

are expanded at their distal ends, and the wide, depressed middle

phalanges are embedded in a broad cutaneous pad, forming the sole of the

foot, on which the animal rests in walking, instead of on the hoofs. The

ungual phalanges are very small and nodular, not flattened on their inner

or opposed surfaces, and not completely encased in hoofs, but bearing

nails on their upper surface only. The cervical region is long and

flexuous, and the vertebræ of which it is composed are remarkable for

the position of the canal for the transmission of the vertebral artery,

which does not perforate the transverse process, but passes obliquely

through the anterior part of the pedicle of the arch (a condition only

found in two other genera of mammals, _Macrauchenia_ and _Myrmecophaga_).

There are no horns or antlers. Though these animals ruminate, the

stomach differs considerably in the details of its construction from

that of the Pecora. The interior of the rumen or paunch has no villi

on its surface, and there is no distinct psalterium or manyplies. Both

the first and second compartments are remarkable for the presence of a

number of pouches or cells in their walls, with muscular septa, and a

sphincter-like arrangement of their orifices, by which they can be shut

off from the rest of the cavity, and into which the fluid portion only

of the contents of the stomach is allowed to enter.[186] The placenta

is diffuse, as in the Suina and Tragulina, not cotyledonary, as in the

Pecora. Finally, the _Camelidæ_ differ not only from other Ungulates,

but from all other mammals, in the fact that the red corpuscles of the

blood, instead of being circular in outline, are oval, as in the inferior

vertebrated classes.

_Camelus._[187]—Dentition of adult: _i_ ¹⁄₃, _c_ ¹⁄₁, _p_ ³⁄₂, _m_ ³⁄₃;

total 34. First upper premolar simple, placed immediately behind the

premaxillæ, and separated by a long diastema from the penultimate tooth

of that series. Lower incisors somewhat proclivous, the outermost the

largest. Skull elongated, with an overhanging occiput, orbits completely

surrounded by bone, and the premaxillæ not articulating with the

arched and somewhat elongated nasals. Vertebræ: C 7, D 12, L 7, S 4, C

13-15. Ears comparatively short and rounded. One or two dorsal adipose

humps. Feet broad, with the toes very imperfectly separated. Tail well

developed, tufted at the end. Hair nearly straight, and not woolly. Size

very large and bulky.

The genus is now represented by two species, viz. the single-humped

Arabian Camel (_Camelus dromedarius_), and the double-humped Bactrian

Camel (_C. bactrianus_, Fig. 114).[188] The former is quite unknown

in a wild state, but it is reported that wild Bactrian Camels occur

in the more remote parts of Turkestan. The latter species is found in

a domesticated state throughout a large portion of Turkestan and the

neighbouring region, extending as far as the Crimea in the west and

to Lake Baikal and Pekin in the east. It is a heavier and more clumsy

animal than the Arabian Camel, with thicker hair, shorter legs, and the

feet more callous and better adapted to a hard ground. The hair is most

developed upon the top of the head, neck, humps, arm, and wrist. Bactrian

Camels are occasionally brought over the stupendous mountain passes south

of Yarkand to within a few days’ journey of Leh, in Kashmir territory.

[Illustration: FIG. 114.—The Bactrian Camel (_Camelus bactrianus_).]

The Arabian Camel is commonly employed as a beast of burden in Africa

and India, and has of late years been introduced into Australia for

the same purpose; it is especially valuable in crossing long stretches

of arid desert from its power of existing for a considerable period of

time without water. The female goes fully eleven months with young, and

produces but a single calf at a birth, which is suckled for a whole

year. In disposition the Camel is surly and subject to furious outbursts

of temper, especially during the rutting season. At such periods the

male utters a peculiar and highly disagreeable bubbling noise in its

throat, well known to all who have travelled in India with Camels as

their transport. It has been said that the Camel is docile, but Palgrave

observes:—

“If docile means stupid, well and good; in such a case the Camel is the

very model of docility. But if the epithet is intended to designate an

animal that takes an interest in its rider so far as a beast can, that

in some way understands his intentions, or shares them in a subordinate

fashion, that obeys from a sort of submissive or half-fellow-feeling with

his master, like the horse or elephant, then I say that the camel is by

no means docile—very much the contrary. He takes no heed of his rider,

pays no attention whether he be on his back or not, walks straight on

when once set agoing, merely because he is too stupid to turn aside,

and then should some tempting thorn or green branch allure him out of

the path, continues to walk on in the new direction simply because he

is too dull to turn back into the right road. In a word, he is from

first to last an undomesticated and savage animal, rendered serviceable

by stupidity alone, without much skill on his master’s part, or any

co-operation on his own save that of an extreme passiveness. Neither

attachment nor even habit impress him; never tame, though not wide-awake

enough to be exactly wild.” The two species breed together freely,

and among the Yourouks of Asia Minor, hybrids, or mules, the produce

generally of a male Bactrian and a female Arabian camel are preferred to

either of the pure breeds.

Fossil remains of Camels are found in the Pliocene of the Siwalik Hills

in Northern India. These differ from the existing representatives of the

genus in having a vertical ridge at the antero-external angle of the

lower molars, whereby they resemble _Auchenia_; their cervical vertebræ

are also intermediate in structure between those of the latter and the

existing Camels. A fossil Camel is also found in the Pleistocene of

Algeria.

_Auchenia._[189]—Dentition of adults normally: _i_ ¹⁄₃, _c_ ¹⁄₁, _p_ ²⁄₂,

_m_ ³⁄₃; total 32—one of the lower premolars may, however, be wanting.

In the upper jaw there is a compressed, sharp, pointed laniariform

incisor near the hinder edge of the premaxilla, followed, in the male at

least, by a moderate-sized, pointed, curved true canine in the anterior

part of the maxilla. The isolated canine-like premolar which follows

in the Camels is not present. The teeth of the molar series, which are

in contact with each other, consist of two very small premolars (the

first almost rudimentary) and three broad molars, constructed generally

like those of _Camelus_. In the lower jaw the three incisors are long,

spatulate, and procumbent; the outer ones being the smallest. Next to

these is a curved, suberect canine, followed after an interval by an

isolated, minute, and often deciduous simple conical premolar; then a

contiguous series of one premolar and three molars, which differ from

those of existing species of _Camelus_ in having a small accessory

column at the anterior outer edge. The skull generally resembles that

of _Camelus_, the relatively larger brain-cavity and orbits and less

developed cranial ridges being due to its smaller size. The nasal bones

are shorter and broader, and are joined by the premaxillæ. Vertebræ:

C 7, D 12, L 7, S 4, C 15-20. Ears rather long and pointed. No dorsal

hump. Feet narrow, the toes being more separated than in the camels,

each having a distinct plantar pad. Tail short. Hairy covering long and

woolly. Size (in existing forms) smaller, and general form lighter than

in the Camels. At present and within historic times the genus is entirely

confined to the western side and southernmost parts of South America, but

fossil remains have been found in the caves of Brazil, in the pampas of

the Argentine republic, and in Central and North America.

[Illustration: FIG. 115.—Llama (_Auchenia glama_), from an animal living

in the Gardens of the Zoological Society of London.]

The word Llama, sometimes spelt Lama, is the name by which the Peruvians

designated one of a small group of closely allied animals, which, before

the Spanish conquest of America, were the only domesticated hoofed

mammals of the country, being kept, not only for their value as beasts

of burden, but also for their flesh, hides, and wool,—in fact, supplying

in the domestic economy of the people the place of the horse, the ox,

the goat, and the sheep of the Old World. The word is now sometimes

restricted to one particular species or variety of the group, and

sometimes used in a generic sense to cover the whole. Although they were

often compared by early writers to sheep, and spoken of as such, their

affinity to the camel was very soon perceived, and they were included

in the genus _Camelus_ in the _Systema Naturæ_ of Linnæus. They were,

however, separated by Cuvier in 1800 under the name of _Lama_, changed

by Illiger in 1811 to _Auchenia_ (in allusion to the great length of

neck, αὐχήν), a term afterwards adopted by Cuvier, and almost universally

accepted by systematic zoologists, although there has been of late a

disposition to revive the earlier name.

In essential structural characters, as well as in general appearance and

habits, all the animals of this genus very closely resemble each other,

so that the question as to whether they should be considered as belonging

to one, two, or more species has been one which has led to a large amount

of controversy among naturalists. The question has been much complicated

by the circumstances of the great majority of individuals which have come

under observation being either in a completely or partially domesticated

state, and descended from ancestors which from time immemorial have been

in like condition, one which always tends to produce a certain amount

of variation from the original type. It has, however, lost much of its

importance since the doctrine of the distinct origin of species has been

generally abandoned.

[Illustration: FIG. 116.—Head of Vicugna, from an animal living in the

Gardens of the Zoological Society of London.]

The four forms commonly distinguished by the inhabitants of South America

are recognised by some naturalists as distinct species, and have had

specific designations attached to them, though usually with expressions

of doubt, and with great difficulties in defining their distinctive

characteristics. These are (1) the Llama, _Auchenia glama_ (Linn.), or

_Lama peruana_ (Tiedemann); (2) the Alpaca, _A. pacos_ (Linn.); (3) the

Guanaco or Huanaco, _A. huanacus_ (Molina); and (4) the Vicugna, _A.

vicugna_ (Molina), or _A. vicunna_, (Cuv.) The first and second are only

known in the domestic state, and are variable in size and colour, being

often white, black, or piebald. The third and fourth are wild, and of

a nearly uniform light-brown colour, passing into white below. They

certainly differ from each other, the Vicugna being smaller, more slender

in its proportions, and having a shorter head (Fig. 116) than the Guanaco

(Fig. 117). It may therefore, according to the usual view of species,

be considered distinct. It lives in herds on the bleak and elevated

parts of the mountain range bordering the region of perpetual snow,

amidst rocks and precipices, occurring in various suitable localities

throughout Peru, in the southern part of Ecuador, and as far south as the

middle of Bolivia. Its manners very much resemble those of the Chamois

of the European Alps; and it is as vigilant, wild, and timid. The wool

is extremely delicate and soft, and highly valued for the purposes of

weaving, but the quantity which each animal produces is not great.

[Illustration: FIG. 117.—Head of Guanaco, from an animal living in the

Gardens of the Zoological Society of London.]

The Guanaco has an extensive geographical range, from the highlands of

the Andean region of Ecuador and Peru to the open plains of Patagonia,

and even the wooded islands of Tierra del Fuego. It constitutes the

principal food of the Patagonian Indians, and its skin is invaluable

to them, as furnishing the material out of which their long robes are

constructed. It is about the size of a European Red Deer, and is an

elegant animal, being possessed of a long, slender, gracefully curved

neck and fine legs. Dr. Cunningham,[190] speaking from observation on

wild animals, says:—

“It is not easy to describe its general appearance, which combines some

of the characters of a camel, a deer, and a goat. The body, deep at the

breast but very small at the loins, is covered with long, soft, very

fine hair, which on the upper parts is of a kind of fawn-colour, and

beneath varies from a very pale yellow to the most beautiful snow-white.

The head is provided with large ears, in general carried well back, and

is covered with short grayish hair, which is darkest on the forehead.

Occasionally the face is nearly black. As a rule it lives in flocks of

from half a dozen to several hundreds, but solitary individuals are now

and then to be met with. They are very difficult to approach sufficiently

near to admit of an easy shot, as they are extremely wary, but, on being

disturbed, canter off at a pace which soon puts a safe distance between

them and the sportsman, even though he should be mounted. Despite their

timidity, however, they are possessed of great curiosity, and will

sometimes advance within a comparatively short distance of an unknown

object, at which they will gaze fixedly till they take alarm, when they

effect a speedy retreat. Their cry is very peculiar, being something

between the belling of a deer and the neigh of a horse. It would be

difficult to overestimate their numbers upon the Patagonian plains; for

in whatever direction we walked we always came upon numbers of portions

of their skeletons and detached bones.”

Darwin, who has given an interesting account of the habits of the Guanaco

in his _Naturalist’s Voyage_, says that they readily take to the water,

and were seen several times at Port Valdes swimming from island to island.

The Llama is only known as a domestic animal, and is chiefly met with

in the southern part of Peru. Burmeister, a very competent writer

on the subject, says that he is perfectly satisfied that it is the

descendant of the wild Guanaco, an opinion opposed to that of Tschudi. It

generally attains a larger size than the Guanaco, and is usually white

or spotted with brown or black, and sometimes altogether black. The

earliest and often-quoted account of this animal by Agustin de Zarate,

treasurer-general of Peru in 1544, will bear repeating as an excellent

summary of the general character and uses to which it was put by the

Peruvians at the time of the Spanish conquest. He speaks of the Llama

as a sheep, observing, however, that it is camel-like in shape though

destitute of a hump:—

“In places where there is no snow the natives want water, and to supply

this they fill the skins of sheep with water and make other living sheep

carry them; for, it must be remarked, these sheep of Peru are large

enough to serve as beasts of burden. They can carry about one hundred

pounds or more, and the Spaniards used to ride them, and they would

go four or five leagues a day. When they are weary they lie down upon

the ground; and as there are no means of making them get up, either by

beating or assisting them, the load must of necessity be taken off.

When there is a man on one of them, if the beast is tired and urged to

go on, he turns his head round and discharges his saliva, which has an

unpleasant odour, into the rider’s face. These animals are of great

use and profit to their masters, for their wool is very good and fine,

particularly that of the species called Pacas, which have very long

fleeces; and the expense of their food is trifling, as a handful of maize

suffices them, and they can go four or five days without water. Their

flesh is as good as that of the fat sheep of Castile. There are now

public shambles for the sale of their flesh in all parts of Peru, which

was not the case when the Spaniards came first; for when one Indian had

killed a sheep his neighbours came and took what they wanted, and then

another Indian killed a sheep in his turn.”

The disagreeable habit here noticed of spitting in the face of persons

whose presence is obnoxious is common to all the group, as may be daily

witnessed in specimens in confinement in the menageries of Europe. One

of the principal labours to which the Llamas were subjected at the time

of the Spanish conquest was that of bringing down ore from the mines in

the mountains. Gregory de Bolivar estimated that in his day as many as

three hundred thousand were employed in the transport of the produce of

the mines of Potosi alone; but since the introduction of horses, mules,

and donkeys the importance of the Llama as a beast of burden has greatly

diminished.

The Alpaca, though believed by many naturalists to be a variety of the

Vicugna, is more probably, like the Llama, derived from the Guanaco,

having the naked callosities on the hind limbs, and the relatively

large skull of the latter. It is usually found in a domesticated or

semi-domesticated state, being kept in large flocks which graze on the

level heights of the Andes of southern Peru and northern Bolivia at an

elevation of from 14,000 to 16,000 feet above the sea-level, throughout

the year. It is smaller than the Llama, and, unlike that animal, is not

used as a beast of burden, but is valued only for its wool, of which the

Indian blankets and ponchas are made. Its colour is usually dark brown or

black.

Mention has already been made of the occurrence of fossil Llamas in

America, but some diversity of view obtains as to the generic position

of some of these forms, owing to variations in their dental formula.

Remains apparently referable to the existing species occur in the

cavern-deposits of Brazil. In the Pleistocene of Mexico we meet with

_A. (Palauchenia) magna_, which attained the size of a Camel, and had

always two, and occasionally three, lower premolars; while in one South

American Pleistocene species, which has been generically separated as

_Hemiauchenia_, there were invariably three premolars in each jaw. In _A.

(Holomeniscus) hesterna_, from the Pleistocene of North America, which

was equal in size to _A. magna_, the premolars were reduced to one in

each jaw; and the same condition obtains in _A. (Eschatius) vitakeriana_,

where, however, the upper one is of simpler structure.

_Extinct Cameloids._—Until within the last few years the existence of

two genera having so very much in common as the Camels and the Llamas,

and yet so completely isolated geographically, had not received any

satisfactory explanation; for the old idea that they in some way

“represented” each other in the two hemispheres of the world was a mere

fancy without philosophical basis. The discoveries made mostly within

the past twenty years of a vast and previously unsuspected extinct fauna

in the American continent of the Tertiary period, as interpreted by

Leidy, Cope, Marsh, and others, has thrown a flood of light upon the

early history of this family, and upon its relations to other mammals.

There have been found in these regions many Camel-like animals exhibiting

different generic modifications; and, what is more interesting, a gradual

series of changes, coinciding with the antiquity of the deposits in which

they are found, have been traced from the thoroughly differentiated

species of the modern epoch down through the Pliocene to the early

Miocene beds, where, their characters having become by degrees more

generalised, they have lost all that specially distinguishes them as

_Camelidæ_, and are merged into forms common to the ancestral type of all

the other sections of the Artiodactyles. Hitherto none of these annectant

forms have been found in any of the fossiliferous strata of the Old

World; and it may therefore be fairly surmised (according to the evidence

at present before us) that America was the original home of the Tylopoda,

and that the true Camels have passed over into the Old World, probably by

way of the north of Asia, where we have every reason to believe there was

formerly a free communication between the continents, and then, gradually

driven southward, perhaps by changes of climate, having become isolated,

have undergone some further special modifications; while those members

of the family that remained in their original birthplace have become,

through causes not clearly understood, restricted solely to the southern

or most distant part of the continent. The occurrence in the dentition of

the fossil Siwalik Camels of a feature now found only in _Auchenia_ is

especially interesting from this point of view.

Briefly referring to some of these fossil types, we may note that

_Pliauchenia_, of the Loup Fork beds (Lower Pliocene) of the United

States, has three lower premolars, while in _Procamelus_ there were four

of these teeth. In _Protolabis_ of the Miocene we have a more generalised

form, in which the dental formula is _i_ ³⁄₃, _c_ ¹⁄₁, _p_ ⁴⁄₄, _m_

³⁄₃; and from this type a transition may be traced to _Poëbrotherium_,

which, while having the same dental formula, was no larger than a Fox,

and had the third and fourth metacarpals separate, with rudiments of the

fourth and fifth. The earliest undoubted representative of the group is

_Leptotragulus_, of the Uinta Eocene, which appears to have been closely

allied to _Poëbrotherium_. It is, however, probable that the first

lower premolar was wanting; while the other premolars of the mandible

were much shorter antero-posteriorly than in the last-named genus. The

manus, moreover, appears to have been less reduced, the second metacarpal

retaining its connection with the magnum. It is suggested that

_Leptotragulus_ may have been derived from the Bunodont genus _Homacodon_

of the Bridger Eocene, mentioned among the _Cænotheriidæ_.

TRAGULINA.

_Family_ TRAGULIDÆ.

No teeth in premaxillæ. Upper canines well developed, especially in

the males; narrow and pointed. Lower canines incisiform. No caniniform

premolars in either jaw, all the premolars except the last in the upper

jaw being secant. Molariform teeth in a continuous series, consisting

of _p_ ³⁄₃, _m_ ³⁄₃. Odontoid process of axis vertebra conical. Fibula

complete. Four complete toes on each foot. The middle metapodials

generally confluent, the outer ones (second and fifth) very slender

but complete, _i.e._ extending from the carpus or tarsus to the digit.

Navicular, cuboid, and ectocuneiform bones of tarsus united. Tympanic

bullæ of skull filled with cancellar tissue. No frontal appendages.

Ruminating, but the stomach with only three distinct compartments, the

manyplies or third cavity of the stomach of the Pecora being rudimentary.

Placenta diffused.

This section is represented only by the single family _Tragulidæ_,

containing a few animals of small size, commonly known as Chevrotains,

intermediate in their structure between the Deer, the Camels, and the

Pigs. The large size of the canines of the male and the absence of

horns caused them to be associated formerly with _Moschus_, one of the

_Cervidæ_; hence they are often spoken of as “Pigmy Musk-Deer,” although

they have no musk-secreting gland, or, except in the above-named trivial

external characters, no special affinities with the true Musk-Deer.

There has scarcely been a more troublesome and obdurate error in zoology

than in this association of animals so really distinct. It has been

troublesome, not only in preventing a just conception of the relations of

existing Artiodactyles, but also in causing great confusion and hindrance

in palæontological researches among allied forms; and most obdurate,

inasmuch as all that has been recently done in advancing our knowledge

of both groups has not succeeded in eradicating it, not only from nearly

every one of our zoological text-books, whether British or Continental,

but even from works of the highest scientific pretensions.

The family is now generally divided into two genera.

_Tragulus_,[191] containing the smallest of the existing Ungulates,

animals having more of the general aspects and habits of some Rodents,

as the Agoutis, than of the rest of their own order. The best-known

species are _T. javanicus_, _T. napu_, _T. stanleyanus_, and _T.

memmina_. The first three are from the Malay Peninsula, or the islands of

the Indo-Malayan Archipelago, the last from Ceylon and India. A fossil

species occurs in the Pliocene of the latter country.

_Dorcatherium_[192] is distinguished chiefly by the feet being stouter

and shorter, the outer toes better developed, and the two middle

metacarpals not ankylosed together. Its dental formula (as that of

_Tragulus_) is usually _i_ ⁰⁄₃, _c_ ¹⁄₁, _p_ ³⁄₃, _m_ ³⁄₃ = 34. Vertebræ:

C 7, D 13, L 6, S 5, C 12-13. The only existing species, _D. aquaticum_

(Fig. 118), from the west coast of Africa, is rather larger than any of

the Asiatic Chevrotains, which it otherwise much resembles, but it is

said to frequent the banks of streams, and have much the habits of Pigs.

It is of a rich brown colour, with back and sides spotted and striped

with white. It is evidently the survivor of a very ancient form, as

remains of the type species (_D. naui_), only differing in size, occur in

the lower Pliocene and Miocene of Europe; fossil species are also found

in the Indian Pliocene. In _D. naui_ there are, at least frequently, four

lower premolars, while the existing species has but three of these teeth.

[Illustration: FIG. 118.—The African Water-Chevrotain (_Dorcatherium

aquaticum_).]

_Extinct Traguloids._—A number of small selenodont Artiodactyles from

various Miocene and Pliocene deposits appear to connect the modern

Tragulina so closely with _Gelocus_ (p. 294), and thus with the ancestral

_Cervidæ_, that their classification is almost an impossibility. Thus

_Leptomeryx_, from the Miocene of the United States, is regarded as a

Traguloid, having four premolars in each jaw and with the metatarsals

fused into a cannon-bone. _Prodremotherium_, of the Upper Eocene

Phosphorites of France, differs in that the metacarpals also form a

cannon-bone; while in the American _Hypertragulus_, both metacarpals and

metatarsals remain separate. _Bachitherium_, of the French Phosphorites,

apparently presents affinity with _Gelocus_, _Prodremotherium_, and

_Dorcatherium_. In this genus the first of the four lower premolars

assumes the character and function of a canine, the true canine being

incisor-like, and there are traces of minute upper incisors.

PECORA, OR COTYLOPHORA.

No premaxillary teeth or caniniform premolars. Upper canines generally

absent, though sometimes largely developed. Inferior incisors, three on

each side with an incisiform canine in contact with them. Molariform

teeth consisting of _p_ ³⁄₃, _m_ ³⁄₃, in continuous series. Auditory

bullæ simple and hollow within. Odontoid process in the form of a

crescent, hollow above. Distal extremity of the fibula represented by a

distinct malleolar bone of peculiar shape, articulating with the outer

surface of the lower end of the tibia. Third and fourth metacarpals and

metatarsals confluent. Outer or lateral toes small and rudimentary, or

in some cases entirely suppressed; their metapodial bones never complete

in existing forms. Navicular and cuboid bones of tarsus united. Horns or

antlers usually present, at least in the male sex. Left brachial artery

arising from a common innominate trunk, instead of coming off separately

from the aortic arch as in the preceding sections. Stomach with four

complete cavities. Placenta cotyledonous.[193]

[Illustration: FIG. 119.—A shed right antler of the Red Deer (_Cervus

elaphus_), found in an Irish lake. _a_, Brow tine; _b_, bez tine; _c_,

tres tine; _d_, crown or royal tine. (After Owen.)]

The Pecora or true Ruminants form at the present time an extremely

homogeneous group, one of the best-defined and most closely united of any

of the Mammalia. But, though the original or common type has never been

departed from in essentials, variation has been very active among them

within certain limits; and the great difficulty which all zoologists have

felt in subdividing them into natural minor groups arises from the fact

that the changes in different organs (feet, skull, frontal appendages,

teeth, cutaneous glands, etc.) have proceeded with such apparent

irregularity and absence of correlation that the different modifications

of these parts are most variously combined in different members of the

group. It appears, however, extremely probable that they soon branched

into two main types, represented in the present day by the _Cervidæ_ and

the _Bovidæ_,—otherwise the antlered and horned Ruminants. Intermediate

smaller branches produced the existing Musk-Deer and Giraffe, as well as

the extinct _Helladotherium_ inclining to the first-named group, and the

extinct _Sivatherium_, _Brahmatherium_, _Hydaspitherium_, and others more

allied to the latter, although upon the true relationship of these forms

there is a difference of opinion.

[Illustration: FIG. 120.—Head of Deer (_Cervus schomburgki_), showing

antlers. From Sclater, _Proc. Zool. Soc._ 1877, p. 682.]

The earliest forms of true Pecora, as _Palæomeryx_, generally had no

frontal appendages, and some few forms continue to the present day in a

similar case. In the very large majority, however, either in both sexes

or in the male only, a pair or occasionally two pairs (_Tetraceros_ and

the extinct _Sivatherium_) of processes are developed from the frontal

bones as weapons of offence and defence, these being almost always formed

on one or other of two types.

1. “Antlers” are outgrowths of true bone, covered during their growth

with vascular, sensitive integument coated with short hair. When the

growth of the antler is complete, the supply of blood to it ceases, the

skin dies and peels off, leaving the bone bare and insensible, and after

a time, by a process of absorption near the base, it becomes detached

from the skull and is “shed” (Fig. 119). A more or less elongated portion

or “pedicle” always remains on the skull from the summit of which a new

antler is developed. In the greater number of existing species of Deer

this process is repeated with great regularity at the same period of each

year. The antler may be simple, straight, subcylindrical, tapering and

pointed, but more often it sends off one or more branches called “tines”

or “snags” (Fig. 119). In this case the main stem is termed the “beam.”

Commonly all the branches of the antler are cylindrical and gradually

tapering. Sometimes they are more or less expanded and flattened, the

antler being then said to be “palmated.” In young animals the antlers

are always small and simple, and in those species in which they are

variously branched or palmated, this condition is only gradually acquired

in several successive annual growths. An interesting parallel has been

observed here, as in so many other cases, between the development of the

race and that of the individual. Thus the earliest known forms of Deer,

those of the Lower Miocene, generally have no antlers, as in the young of

the existing species. The Deer of the Middle Miocene have simple antlers,

with not more than two branches, as in existing Deer of the second

year; but it is not until the Pliocene and Pleistocene times that Deer

occur with antlers developed with that luxuriance of growth and beauty

of form characteristic of some of the existing species in a perfectly

adult state. Among recent _Cervidæ_, antlers are wanting in the genera

_Moschus_ and _Hydropotes_; they are present in both sexes in _Tarandus_

(the Reindeer), and in the male sex only in all others.

In those forms with the most complex antlers (Figs. 119, 120) the tine

immediately over the forehead is termed the _brow tine_, the next one

the _bez tine_, and the third one the _tres tine_; the mass of points at

the summit of the antler being termed either the _royal_ and _surroyal

tines_, or collectively the _crown_. The nodulated bony ring at the base

of the antler, just above the point at which it separates from the

pedicle when it is shed, is termed the _burr_.

[Illustration: FIG. 121.—Head of Antelope (_Gazella granti_), showing

horns. From Sir V. Brooke, _Proc. Zool. Soc._ 1878, p. 724.]

2. The horns of the _Bovidæ_ consist of permanent, conical, usually

curved bony processes, into which air-cells continued from the frontal

sinuses often extend, called “horn-cores,” ensheathed in a case of

true horn, an epidermic development of fibrous structure, which grows

continuously, though slowly, from the base, and wears away at the apex,

but is very rarely shed entire. The only existing species in which

the latter process occurs regularly and periodically is the American

Prong-Buck (_Antilocapra_), in which the horns also differ from those of

all others in being bifurcated. Horns are not present at birth, but begin

to grow very soon afterwards. The males of all existing _Bovidæ_ possess

them, and they are also present (though usually not so fully developed)

in the females of all except the genera _Boselaphus_, _Strepsiceros_,

_Tragelaphus_, _Antilope_, _Æpyceros_, _Saiga_, _Cobus_, _Cervicapra_,

_Pelea_, _Nanotragus_, _Neotragus_, _Cephalophus_, and _Tetraceros_; as

well as in some species of _Gazella_, such as _G. picticandata_ and _G.

walleri_.

[Illustration: FIG. 122.—Crown surface of a worn left upper molar

of _Palæomeryx sivalensis_, to show brachydont type. (From the

_Palæontologia Indica_.)]

Another character by which different members of the _Pecora_ can be

distinguished among themselves is derived from the nature of the molar

teeth. Although there is nothing in the general mode and arrangement of

the enamel-folds, or in the accessory columns, absolutely distinctive

between the two principal families, existing species may generally be

distinguished, inasmuch as the true molars of the _Cervidæ_ are more or

less brachydont, and those of the _Bovidæ_ generally hypsodont, _i.e._,

the teeth of the former have comparatively short crowns (Fig. 122),

which, as in most mammals, take their place at once with the neck (or

point where the crown and root join) on a level with or a little above

the alveolar border, and remain in this position throughout the animal’s

life; whereas in the other forms (Fig. 123), the crown being lengthened

and the root small, the neck does not come up to the alveolar level

until a considerable part of the surface has worn away, and the crown

of the tooth thus appears for the greater part of the animal’s life

partially buried in the socket. In this form of tooth (which is almost

always most developed in the posterior molars of the permanent series)

the constituent columns of the crown are necessarily nearly parallel,

whereas in the first-described they diverge from the neck towards the

free or grinding surface of the tooth. In the completely hypsodont form

the interstices of the lengthened columnar folds of enamel and dentine

are filled up with cement, which gives stability to the whole organ,

and is entirely or nearly wanting in the short-crowned teeth. The same

modification from low to high crowns without essential alteration of

pattern is seen in an even still more marked manner in some of the

Perissodactyle Ungulates, the tooth of the Horse bearing to that of

_Anchitherium_ the same relation as that of an Ox does to the early

selenodont Artiodactyles. A parallel modification has also taken place in

the molar teeth of the Proboscidea.

[Illustration: FIG. 123.—Inner and outer aspects of an almost unworn left

upper molar of the Nilghai (_Boselaphus tragocamelus_), to show hypsodont

type. (From the _Palæontologia Indica_.)]

As the hypsodont tooth is essentially a modification of, and, as it were,

an improvement upon, the brachydont, it is but natural to expect that

all intermediate forms may be met with. Even among the Deer themselves,

as pointed out by Lartet, the most ancient have very short molars, and

the depressions on the grinding surface are so shallow that the bottom

is always visible; while in the _Cervidæ_ of the more recent Tertiary

periods, and especially the Pleistocene and living species, these same

cavities are so deep that whatever be the state of the dentition the

bottom cannot be seen. Some existing Deer, as the Axis, are far more

hypsodont than the majority of the family; and, on the other hand,

many of the Antelopes (as _Tragelaphus_) retain much of the brachydont

character, which is, however, completely lost in the more modern and

highly specialised Sheep and Oxen.

[Illustration: FIG. 124.—Stomach of Ruminant opened to show internal

structure. _a_, Œsophagus; _b_, rumen or paunch; _c_, reticulum or

honey-comb bag; _d_, psalterium or manyplies; _e_, abomasum or reed; _f_,

duodenum.]

The complicated stomach of the Pecora (Fig. 124), which is necessary for

the performance of the peculiar function known as “chewing the cud”—a

function common also to the Tragulina and Tylopoda—is divided into four

well-defined compartments, known as (1) the Rumen or Paunch, (2) the

Reticulum or Honey-comb Bag, (3) the Psalterium or Manyplies, (4) the

Abomasum or Reed. The paunch is a very capacious receptacle, shaped

like a blunted cone bent partly upon itself. Into its broader base

opens the œsophagus or gullet at a spot not far removed from its wide

orifice of communication with the second stomach or honey-comb bag. Its

inner walls are nearly uniformly covered with a pale mucous membrane,

which is beset with innumerable close-set, short, and slender villi,

resembling very much the “pile” on velvet. The honey-comb bag is very

much smaller than the paunch. It is nearly globose in shape, and receives

its name on account of the peculiar arrangement of its mucous membrane

which forms shallow hexagonal cells all over its inner surface. Running

along its upper wall there is a deep groove, coursing from the first to

the third stomach. This groove plays an important part in the act of

rumination. Its walls are muscular, like those of the viscus with which

it is associated, which allows its calibre to be altered. Sometimes it

completely closes round so as to become converted into a tube by the

opposition of its edges. At others it forms an open canal. The manyplies

is globular in form, and its lining membrane is raised into longitudinal

folds or laminæ arranged very much like the leaves of a book, and very

close together. Their surfaces are roughened by the presence of small

projections or papillæ. The reed is the proper digestive stomach,

corresponding with the same organ in man. Its shape is somewhat pyriform,

and its walls are formed of a smooth mucous membrane, which secretes the

gastric juice.

When the food is first swallowed it is conveyed into the paunch, and

after undergoing a softening process there it is regurgitated into

the mouth, and undergoes a further trituration by the molar teeth and

mixture with the secretion of the salivary and buccal glands. It is then

swallowed again, but now passes directly through the before-mentioned

groove into the manyplies, and, after filtering through the numerous

folds of the lining membrane of this cavity, finally reaches the fourth

or digestive stomach.

The placenta of the Pecora is characterised by the fœtal villi being

collected into groups or cotyledons, which may present either a convex

or a concave surface to the uterus. These cotyledons are received into

permanent elevations in the mucous membrane of the uterus, the surfaces

of which present a curvature which is the reverse of the cotyledons.

_Family_ CERVIDÆ.

Frontal appendages, when present, in the form of antlers. First molar,

at least, in both jaws brachydont. Two orifices to the lachrymal duct,

situated on or inside the rim of the orbit. An antorbital or lachrymal

vacuity of such dimensions as to exclude the lachrymal bone from

articulation with the nasal. Upper canines usually present in both

sexes and sometimes attaining a very great size in the male (see Fig.

134). Lateral digits of both fore and hind feet, almost always present,

and frequently the distal ends of the metapodials. Placenta with few

cotyledons. Gall-bladder absent (except in _Moschus_). This family

contains numerous species, having a wide geographical distribution,

ranging in the New World from the Arctic Circle as far south as Chili,

and in the Old World throughout the whole of Europe and Asia, though

absent in the Ethiopian and Australian regions.

It may be divided into two subfamilies.

Subfamily =Moschinæ=.—This subfamily is represented solely by the

Musk-Deer, which differs so remarkably from the true Deer that it is

considered by several writers as the representative of a separate family.

The late Professor Garrod even suggested that it should be regarded as an

extremely aberrant member of the _Bovidæ_.

[Illustration: FIG. 125.—The Musk-Deer (_Moschus moschiferus_).]

_Moschus._[194]—The Musk-Deer (Fig. 125) in many respects stands by

itself as an isolated zoological form, retaining characters belonging

to the older and more generalised types of ruminants before they were

distinctly separated into the horned and the antlered sections now

dominant upon the earth. One of these characters is that both sexes are

entirely devoid of any sort of frontal appendage. In this, however,

it agrees with one existing genus of true Deer (_Hydropotes_); and,

as in that animal, the upper canine teeth of the males are remarkably

developed, long, slender, sharp pointed, and gently curved, projecting

downwards out of the mouth with the ends turned somewhat backwards.

Vertebræ: C 7, D 14, L 5, S 5, C 6. Among the anatomical peculiarities in

which it differs from all true Deer and agrees with the _Bovidæ_ is the

presence of a gall-bladder. The hemispheres of the brain are but slightly

convoluted, and the cotyledons of the placenta are arranged in a peculiar

linear manner.[195]

Although, owing to variations of colour presented by different

individuals in different localities and seasons, several nominal species

have been described, zoologists are now generally agreed that there is

but one, the _Moschus moschiferus_ of Linnæus. In size it is rather

less than the European Roe Deer, being about 20 inches high at the

shoulder. Its limbs, especially the hinder ones, are long. The feet are

remarkable for the great development of the lateral pair of hoofs, and

for the freedom of motion they all present, so that they appear to have

the power of grasping projecting rocky points,—a power which must be

of great assistance to the animal in steadying it in its agile bounds

among the crags of its native haunts. The ears are large, and the tail

quite rudimentary. The hair covering the body is long, coarse, and of a

peculiarly brittle and pith-like character, breaking with the application

of an extremely slight force; it is generally of a grayish-brown colour,

sometimes inclined to yellowish-red, and often variegated with lighter

patches. The Musk-Deer has a wide distribution over the highlands

of central and eastern Asia, including the greater part of southern

Siberia, and extends to Kashmir on the south-west and Cochin-China on

the south-east, always, however, at considerable elevations,—being

rarely found in summer below 7000 feet above the sea-level, and ranging

as high as the limits of the thickets of birch or pines, among which

it mostly conceals itself in the daytime. It is a hardy, solitary, and

retiring animal, chiefly nocturnal in its habits, and almost always found

alone, rarely in pairs, and never in herds. It is exceedingly active

and sure-footed, having few equals in traversing rocky and precipitous

ground; and it feeds on moss, grass, and leaves of the plants which grow

on the mountains among which it makes its home.

Most of the animals of the group to which the Musk-Deer belongs, in

fact the large majority of mammals, have some portion of the cutaneous

surface peculiarly modified and provided with glands secreting some

odorous and oleaginous substance specially characteristic of the species.

This, correlated with the extraordinary development of the olfactory

organs, appears to offer the principal means by which animals in a

state of nature become aware of the presence of other individuals of

their own species, or of those inimical to them, even at very great

distances, and hence it is of extreme importance both to the well-being

of the individual and to the continuance of the race. The situation of

this specially modified portion of skin is extremely various, sometimes

between the toes, as in Sheep, sometimes on the face in front of the

eyes, as in many Deer and Antelopes. Sometimes it is in the form of a

simple depression or shallow recess, often very deeply involuted, and in

its fullest state of development it forms a distinct pouch or sac with

a narrow tubular orifice. In this sac a considerable quantity of the

secretion can accumulate until discharged by the action of a compressor

muscle which surrounds it. This is the form taken by the special gland of

the Musk-Deer, which has made the animal so well known, and has proved

the cause of an unremitting persecution to its possessor. It is found

in the male only, and is a sac about the size of a very small orange,

situated beneath the skin of the abdomen, the orifice being immediately

in front of the preputial aperture. The secretion with which the sac is

filled is of dark-brown or chocolate colour, and when fresh described as

being of the consistence of “moist gingerbread,” but becoming dry and

granular after keeping. It has a peculiar and very powerful scent, which

when properly diluted and treated forms the basis of many of our most

admired perfumes. When the animal is killed the whole gland or “pod” is

cut out and dried, and in this form reaches the market of the Western

World, chiefly through China.

Subfamily =Cervinæ.=—This subfamily includes all the true Deer. According

to the arrangement proposed by Sir V. Brooke[196] the existing _Cervinæ_

may be divided into the sections Plesiometacarpalia and Telemetacarpalia.

=Plesiometacarpalia.=—In this section, which is mainly characteristic of

the Old World, the proximal portions of the lateral (second and fifth)

metacarpals persist, and the vomer is never so ossified as to divide the

posterior osseous nares into two distinct passages. The premaxillæ nearly

always articulate with the nasals.

_Cervulus._[197]—Antlers half the length of the head, placed on pedicles

nearly equal to them in length. Brow tine short, inclined inwards and

upwards; terminal extremity of beam unbranched, and curved downwards and

inwards. Lachrymal fossa of skull very large, and extending into facial

part of jugal; lachrymal (antorbital) vacuity moderate. Ascending portion

of premaxillæ at least as long as nasals. A permanent ridge extending

from each pedicle over the orbit, lachrymal fossa and vacuity. Auditory

bulla much inflated. Upper canines of males very large. Ectocuneiform

united with naviculo-cuboid of tarsus. No traces of the phalanges of the

lateral digits.

The native name Muntjac has been generally adopted in European languages

for a small group of Deer indigenous to the southern and eastern parts

of Asia and the adjacent islands, which are separated by very marked

characters from all their allies. They are also called “Kijang” or

“Kidjang,” and constitute the genus _Cervulus_ of Blainville and most

zoologists;—_Styloceros_ of Hamilton-Smith, and _Prox_ of Ogilby. They

are all of small size compared with the majority of Deer, and have long

bodies and rather short limbs and neck. The antlers, which as in most

Deer are present in the male only, are small and simple, and the main

stem or beam, after giving off a very short brow tine, inclines backwards

and upwards, is unbranched and pointed, and when fully developed curves

inwards and somewhat downwards at the tip. These small antlers are

supported upon pedicles or permanent processes of the frontal bones,

longer than in any other Deer, and the front edges of which are continued

downwards as strong ridges passing along the sides of the face above the

orbits, and serving to protect the large supraorbital glands lying on

their inner sides. The lachrymal fossa of the skull, in which is lodged

the large suborbital gland or crumen, is of great depth and extent. The

upper canine teeth of the males are strongly developed and sharp, curving

downwards, backwards, and outwards, projecting visibly outside the mouth

as tusks, and loosely implanted in their sockets. In the females they are

very much smaller. The limbs exhibit several structural peculiarities

not found in other Deer. The lateral digits of both fore and hind feet

are very little developed, the hoofs alone being present and their bony

supports (found in all other Deer) wanting. There is a tufted gland on

the outer side of the metatarsus.

The Muntjacs are solitary animals, very rarely even two being seen

together. They are fond of hilly ground covered with forests, in the

dense thickets of which they pass most of their time, only coming to

the skirts of the woods at morning and evening to graze. They carry the

head and neck low and the hind-quarters high, their action in running

being peculiar and not very elegant, somewhat resembling the pace of a

sheep. Though with no power of sustained speed or extensive leap, they

are remarkable for flexibility of body and facility of creeping through

tangled underwood. They are often called by Indian sportsmen “Barking

Deer,” a name given on account of their alarm cry, a kind of short shrill

bark, like that of a fox but louder, which may often be heard in the

jungles they frequent both by day and by night. When attacked by dogs the

males use their sharp canine teeth with great vigour, inflicting upon

their opponents deep and even dangerous wounds.

There is some difference of opinion among zoologists as to the number of

species of the genus _Cervulus_. Sir Victor Brooke, who investigated this

question in 1878 (see _Proceedings of the Zoological Society of London_

for that year, p. 898), came to the conclusion that there are certainly

three which are quite well marked, viz.—

_C. muntjac_ (Fig. 126), found in British India, Burma, the Malay

Peninsula, Sumatra, Java, Hainan, Banca, and Borneo. The general colour

is a bright yellowish-red, darker in the upper parts of the back; the

fore legs from the shoulder downwards and the lower part of the hind

legs, dark bluish-brown; anterior parts of the face from the muzzle to

between the eyes, brown—a blackish line running up the inside of each

frontal ridge; chin, throat, inside of hind legs, and under surface of

tail white. The female has a black bristly tuft of hair on the spot from

which the pedicles of the antlers of the male grow. The average length

of the male, according to Jerdon, is 3½ feet, tail 7 inches, height 26

to 28 inches. The female is a little smaller. The specimens from Java,

Sumatra, and Borneo are of larger size than those from the mainland, and

may possibly be of distinct species or race.

[Illustration: FIG. 126.—The Muntjac (_Cervulus muntjac_).]

_C. lacrymans_ of Milne-Edwards, or Sclater’s Muntjac of Swinhoe, from

Moupin, and near Hangchow, China.

_C. reevesi_, a very small species from southern China.

Subsequently the name _C. crinifrons_ has been applied to a Muntjac

from Ningpo, China, readily distinguished from all other species by its

bushy forehead and long tail. Another species from Tenasserim has been

described as _C. feæ_.

Small Deer from the European Pliocene have been provisionally referred

to _Cervulus_, but the so-called _Prox furcatus_, of the Miocene, is now

included in _Palæomeryx_.

_Elaphodus._[198]—Antlers very small, unbranched, supported on long,

slender, converging pedicles. Ascending rami of premaxillæ shorter than

nasals. No supraorbital ridges or frontal glands. Upper canines of male

long, but not everted. A distinct frontal tuft of hair. Other characters

as in _Cervulus_.