_Ovis nahura_ is chiefly responsible for the impossibility of strictly
separating the Sheep and Goats. It has no suborbital glands or lachrymal
fossae, which are as a rule present in the Sheep and absent from the Goats.
On the other hand interdigital glands are present, which is the case with
Sheep. Its habits, too, are a blending of those of the Sheep and the Goat.
It lives largely on undulating ground like Sheep, and frequently lies down
during the day on its feeding ground. On the other hand it is, like the
Goats, a splendid climber.
The Goats, genus _Capra_, differ from the Sheep in their slighter build and
in the fact that the horns are not spirally curved, but arched over the
back. There is also the characteristic beard, {325} and the male is
odorous. The true Goats are almost exclusively Palaearctic in range. They
show the limited distribution of the Sheep, a distribution which follows
from their mountain-loving habits.
[Illustration]
FIG. 175.--Sinaitic Ibex. _Capra sinaitica._ x 1/10.
Thus we have the Spanish Ibex (_C. pyrenaica_), limited to the Pyrenees and
other mountain ranges of the peninsula; _C. ibex_, the Steinbok of the Alps
and the Tyrol; the Markhoor, _C. falconeri_, of certain mountain ranges of
Afghanistan; the Caucasian, Sinaitic, and Cretan Ibexes, and the Thar.
_Capra aegagrus_, the Persian Wild Goat, ranges from the Caucasus to Sind.
It is this animal which produces the true "bezoar stone." The substance in
question is a secretion apparently found in the stomach. It is still,
according to Mr. Blanford, regarded as an antidote to poison in Persia.
Buffon called this Goat the "Pasan," which is evidently a corruption of the
word bezoar. When the substance was in repute as a medicine of the
"alexipharmic" kind, the supply naturally came up to the demand. Thus the
bezoar stones of the Lama in South America gained repute, and there were
"Oriental bezoar, cow {326} bezoar, hog bezoar, and monkey bezoar"! As
concretions of one kind or another are not uncommon objects in the
alimentary tract of mammals it was easy enough to obtain a fair amount of
some substance which was sure to sell well. It is said that a stone
weighing four ounces was once sold in this country (or at any rate in
Europe) for L200.
"There can be no doubt," observes Mr. Blanford, "that _C. aegagrus_ is one
of the species, and probably the principal, from which tame goats are
derived."
[Illustration]
FIG. 176.--Japanese Goat Antelope. _Nemorrhaedus crispus._ x 1/12. (From
_Nature_.)
The Chamois (_Rupricapra_) and the Goral (_Nemorrhaedus_) are best
described as Goat-like Antelopes; but, as already said, it is difficult to
split up the Bovidae satisfactorily. The Rocky Mountain Goat, _Haploceros
montanus_, is a large Goat-like creature, {327} which has the peculiarity
of having the shortest cannon bones of any Ruminant. Its name denotes its
range.
[Illustration]
FIG. 177.--Goral. _Nemorrhaedus goral._ x 1/12. (From _Nature_.)
The Musk Ox, _Ovibos moschatus_, has been thought to be on the borderland
between the Sheep and Oxen, as indeed expressed in its scientific name. It
is a purely Arctic creature, now confined to the Nearctic region; but it
formerly existed in the Arctic regions of Europe.
The anatomy of the "soft parts" of this genus has lately been investigated
by Dr. Loennberg.[218] The animal has no foot glands such as occur in
_Ovis_. Its kidneys, however, are non-lobate, and it has orbital glands.
The cotyledons of the placenta are unusually large, and the cow has the
"primary four" teats. It cannot, in fact, be definitely referred to either
the Caprine or the Bovine section of the Cavicornia, and while possibly
most allied to _Budorcas_, it may be regarded, at least for the present, as
entitled to form a separate sub-family of its own. The muzzle {328} has a
slight naked strip above the nostrils, as in the Sheep, but there is no
fissure of the upper lip.
EXTINCT FAMILIES OF ARTIODACTYLA.
The origin of the Artiodactyla is placed by Cope in the family
PANTOLESTIDAE,[219] allied to the genus _Protogonodon_ of the Condylarthra.
As, however, this family is represented by but a few back teeth and a
fragment of the hind-foot, it seems premature to regard it as the necessary
starting-point of the Bunodont and Ruminant groups.
FAM. ANTHRACOTHERIIDAE.--This well-known and ancient family consists of
creatures of for the most part a Pig-like form, with teeth approaching the
selenodont shape, and a complete dentition. The carpals, tarsals,
metacarpals, and metatarsals are all free. The toes are four (or five) to
each foot, with the outermost beginning to be reduced. These of course are
all generalised and primitive characters, pointing nowhere in particular,
except, of course, to an Artiodactyle stock, on account of the teeth and
the two predominating toes.
The type genus of the family, _Anthracotherium_, is not, as its name might
seem to denote, a relic of the Carboniferous period; its remains were found
in lignite, which may also show that it was at least semi-aquatic in habit.
Its form, however, must have been Pig-like, so at least one would presume
from the elongated skull and shortish legs. There were species as great as
a Rhinoceros, and smaller forms. The genus began in the Oligocene and
continued down to the Pliocene. It is known from Europe, Asia, and America.
The skull is long with a prominent sagittal crest. The facial part is also
very long, and the orbits are not closed by a bony ring. The premolars are
simple teeth; the molars distinctly bunodont with a tendency in one or two
to the selenodont condition. The canines are powerful, as are also the
incisors. The scapula has been specially compared with that of the Camel.
It has no acromion, which is usually though not always absent in Ungulates.
An ally of the present animal, for instance, the Hippopotamus, has the
acromion developed. The radius and ulna, the tibia and fibula, are all
fully developed. {329}
_Ancodus_ (or _Hyopotamus_, as it has been called) is also Oligocene in
range, and its remains have been found in the same countries as have those
of _Anthracotherium_. Both genera are indeed closely allied. _Ancodus_
seems to be a more slightly-built creature. The skull looks weaker, but
presents much the same features of organisation. In _A. velaunus_, a
species found in French rocks, a metacarpal of digit I. was present in the
manus, while _A. brachyrhynchus_ had a completely five-fingered manus.
The Miocene genus _Merycopotamus_ (from the lower layers of the Siwalik
formation in India) is more distinctly selenodont than the forms already
discussed. On this ground it has been placed in a separate sub-family. As,
however, in other respects it does not depart from the Anthracotherian type
of structure, this proceeding seems to be hardly necessary. There are two
species known, of which one, _M. nanus_, is, as its name denotes, a dwarf
form.
FAM. CAENOTHERIIDAE.--While the last family consisted of animals rather
more akin to the Pigs, the present is more Pecorine in its characters. The
molars are selenodont; but as in the Tragulidae the premolars are more of
the nature of cutting teeth. The dentition, like that of so many of these
early Ungulates, is complete, and the canines are not prominent. The feet
are four-toed, the lateral toes not reaching the ground.
The principal genus is the Eocene and Miocene _Caenotherium_. Of this genus
there were a considerable number of species all European in range, and of
small size--not more than a foot or so in length. Their small size is
suggestive of the Chevrotains. In the skull the orbital cavity is nearly or
quite surrounded by bone, and the tympanic bulla is large and inflated. A
common feature of Artiodactyles, a failure of the nasals and maxillae to
meet at the side of the face, is to be seen in this ancient forerunner of
the Pecora.
_Plesiomeryx_, also European, and from the same geological horizon, is a
very closely allied form.
FAM. XIPHODONTIDAE.--This family consists of slender, small Artiodactyles
which are, like the Caenotheriidae, related to the Pecora. They are
confined in their range to Europe.
The type genus _Xiphodon_ has selenodont molars and elongated, slender,
cutting premolars. The dentition was complete and the canines not highly
developed. Like _Caenotherium_, {330} _Xiphodon_ was a hornless creature,
but with only two toes, the two lateral digits being represented by the
merest rudiments of metacarpals. The other metacarpals were unusually long.
_Amphimeryx_ (also called _Xiphodontotherium_) is much more imperfectly
known, but belongs to this family or to that of the Caenotheriidae.
_Dichodon_ is another member of the same family.
FAM. OREODONTIDAE.--This family, consisting of numerous genera, is limited
to the North American continent. Its range in time is from the Eocene to
the Lower Pliocene. The family as a whole is to be distinguished by a
number of primitive characters. The dentition is complete; the feet are
four- or even five-toed; the orbit is sometimes open behind. The canines of
the lower jaw are not more pronounced than the incisors. The
characteristics of the group will be further developed by a consideration
of some of the principal genera which are included in this family.
_Oreodon_ is a Miocene form about as large as a Peccary. The skull has a
short face with a completely-closed orbital cavity. In front of the orbit
is a deep pit, not a mere deficiency of ossification, such as occurs in
many Artiodactyles. This is placed on the lachrymal bone, and is in fact a
lachrymal fossa, such as occurs in other forms. The odontoid process of the
axis vertebra is somewhat cheese-taster shaped, as in recent Artiodactyles.
There are fourteen dorsal vertebrae and a very large number of caudals. The
radius and the ulna are completely separated, as are the carpals. There are
five digits to the fore-limbs. The fibula is complete and independent. The
hind-foot is four-toed. Several species of the genus are known.
_Merycochoerus_ is an allied Miocene genus. It is more massive in form than
the last, but otherwise does not present differences of importance.
_Mesoreodon_ is another genus of this family which presents some curious
features of organisation. In the skull and teeth there is nothing very
noteworthy, but the hyoid is remarkable. This appendage of the skull is by
no means always preserved, and when it is, it might be denied that it
belonged to any particular skull. In the present case there appears to be
no doubt as to the identity of the bones, which resemble the corresponding
bones of the Perissodactyla much more than they do those of other
Artiodactyles. Associated with the bones an ossified {331} thyroid
cartilage of the larynx was found. As the skull was that of a male, this
character may be a sexual one. It is quite comparable to the ossification
of the same cartilage in the American monkey _Callithrix_. "The function of
the bone," observes Professor Scott,[220] "was probably similar to that
performed by the enormously-inflated basihyal of the howling monkeys, and
must have given to these animals most unusual powers of voice." Another
important anatomical fact about _Mesoreodon_ is the apparent existence of a
clavicle. It is of course conceivable that the remains of some other animal
have got mixed up with that of the individuals upon which the present genus
is founded; but failing that, here is a clavicle in an Ungulate. The spine
of the scapula possesses a metacromion. This greater development of the
spine of the scapula in Artiodactyles than in Perissodactyles is, it is
suggested, to be correlated with the earlier loss of the clavicle in the
latter group of Ungulates.
_Cyclopidius_ (synonymous with _Brachymeryx_) is a kind of pug form of
_Oreodon_. The skull is short and broad, and the end of the snout a little
turned up. The upper incisors are small and drop out early. On each side of
the nasals is a large oval vacuity which is perhaps to be compared to the
lateral deficiency to be found in other Artiodactyles. One species of this
singular-looking form is appropriately called _C. simus_.
Other allied genera are _Merychyus_ and _Leptauchenia_. The former extends
as far down as the Lower Pliocene, and is thus one of the newest forms of
Oreodontidae.
_Agriochoerus_[221] (Fig. 178) is placed in a separate sub-family from the
types which have just been considered. It is Miocene in range. It differs
from _Oreodon_ and its closer relatives by the fact that the orbit is open
behind and not closed. The most remarkable fact about this creature is that
the terminal phalanges of the digits (five in the fore- and four in the
hind-feet) being pointed, seem to suggest their encasement with claws
rather than hoofs. The pollex, though small, seems to have been opposable.
As with other Oreodonts, the molars are selenodont. The premaxillae are
toothless--at least in adults, for two teeth are present in the {332}
young. There are several species. _Agriochoerus_, like _Oreodon_ and
primitive Ungulates in general, had a long tail. The genus thus shows a
mixture of ancient and specialised characters.
[Illustration]
FIG. 178.--Skeleton of _Agriochoerus latifrons_. x 1/8. (After Wortman.)
The most ancient form of Oreodont is _Protoreodon_. This is Eocene, and
became extinct during that period. It had a complete dentition, open orbit,
and no lachrymal fossa. The fore-feet were five-toed, the hind four-toed.
FAM. ANOPLOTHERIIDAE.--This family is entirely Eocene in point of time, and
is unknown outside Europe. The dentition of the group is complete; the
molars are seleno-bunodont, like those of the Anthracotheriidae. The bones
of the carpus, tarsus, metacarpus and metatarsus are all free; the toes are
four to two in number on each foot. The orbit is widely open behind. The
tail is long, as in _Xiphodon_, etc. {333}
These general characters only just serve to differentiate the family; but
they illustrate its archaic character, in which it resembles the
Xiphodontidae, and even more the Anthracotheriidae. A survey of some of the
genera which have been assigned to the family will bring out other features
in the organisation of these very ancient Artiodactyles.
_Anoplotherium_ is so called on account of the fact that it is, like all
ancient Artiodactyles, without horns or claws. Tusks it might have, but as
a matter of fact has not. There are, as in Artiodactyles generally,
nineteen dorso-lumbar vertebrae; the long tail has numerous chevrons. The
shoulder blade has a well-marked acromion and a distinct coracoid process;
it is wide proximally. The bones of the fore-arm and fore-leg are, as is
usual in primitive Artiodactyles, separate.
In the skull the chief features, in addition to that mentioned in the
definition of the family, are the large size of the paroccipital processes;
there is no fossa lachrymalis or deficiency in the side of the face. The
animal is three-toed, both in the fore- and hind-limbs. The second toe is
nearly as large as the Artiodactyle third and fourth. There are tiny
rudiments of the two remaining fingers. The hind-foot is also three-toed,
and there is a trace of the hallux. The fingers are so widely separated and
divergent from each other that it has been suggested that the animal had
webbed feet and inhabited marshes, in which it swam by the aid of its long
tail. The creature was the size of a Tapir.
Closely resembling _Anoplotherium_ are a number of other genera.
_Diplobune_ ( = _Hyracodontotherium_) was much like the last, but was a
more delicately-formed animal. The fingers and toes (three of each) end in
such sharply-pointed phalanges that claws seem to be almost suggested.
There are several species of this genus. _Dacrytherium_ differs by the
presence of a lachrymal fossa.
_Dichobune_ has four-toed extremities, of which the lateral ones are more
slender and shorter than the two middle ones. As in other Anoplotheriidae,
the anterior premolars are furnished with a sharp cutting edge.
ORDER V. SIRENIA.
Aquatic Mammalia, with but few scattered hairs; hind-limbs absent;
fore-limbs paddle-shaped; tail flattened, and either {334} Whale-like or
rhomboidal to circular in form. Nostrils on upper surface of not
specially-elongated snout. Clavicles are absent. The scapula has the normal
mammalian form, with a well-developed and roughly median spine. The bones
of the arm and hand articulate together, as in land animals; the phalanges
show at most traces of increase in number above the normal. Pelvis
represented by a vestige, more highly developed in some fossil than in
recent forms. Stomach complex, consisting of several chambers. Lungs simple
and not lobulated. Diaphragm oblique and very muscular. Brain peculiar in
form and but slightly convoluted. Testes abdominal. Teats two, and pectoral
in position. Placenta non-deciduous and zonary.[222]
This limited group consists of purely aquatic forms, which are both marine
and fresh-water in their proclivities. They have been placed in the
immediate vicinity of the Whales; but it is now believed by most zoologists
that the likenesses which they undoubtedly show to the Cetacea are of an
adaptive kind and related to their similar mode of life. The group is a
readily-definable one. Externally they are marked by their dark coloration,
somewhat Whale-like though of clumsier build, and by the total absence of
external ears and hind-limbs; the latter are, however, as will be pointed
out shortly, marked by certain rudimentary bones. There is a flattened
tail, which in the Dugong and _Rhytina_ is precisely like that of a Whale.
It is interesting to note that the former genus, whose tail is, judging it
at least by the standard of the Whales, more completely modified for the
aquatic life, should also show other features which indicate their longer
life as marine creatures. For the flippers are more Whale-like in that the
fore-arm is completely enclosed within the body, or nearly so, and the
nostrils have a more decidedly superior position than in the Manatee. The
fore-limbs of this group, as may be inferred from what has just been said,
are flipper-like; but, contrary to what we find in Whales, the phalanges do
not as a rule show any traces of multiplication, so characteristic a
feature of the Cetacean hand, and the individual bones are connected by
well-formed joints. Beneath the thick skin, which is sparsely provided with
stout hairs in the Dugong, is a layer of blubber. Dr. Murie has called
attention to the fact that this layer in the {335} Manatee[223] differs
from the blubber of the Whale in that there is no free oil anywhere.[224]
The skeleton of the Sirenia is strong and massive, thus contrasting with
the loosely-textured bones of the Cetacea. The cervical vertebrae are, as a
rule, free, but the second and third are fused in _Manatus_ and the extinct
_Halitherium_. It is noteworthy that in _Rhytina_ the cervical vertebrae
have the exceedingly thin centra that characterises the neck vertebrae in
Whales. The ribs are most of them firmly articulated by two heads. The
breastbone is generally reduced, as in Whales; and but few ribs are
attached thereto. The vertebrae, moreover, are well locked together by
zygapophyses, and not loosely attached as in Whales.
The shoulder blade is long and narrow, and not unlike that of the Seals. It
is totally unlike the peculiarly-modified scapula of the Whale tribe. But,
as in the latter, there are no clavicles.
The hind-limbs are only represented by the pelvis; and this is a
rudimentary structure, varying, however, in the degree of its degeneration.
That of the extinct _Halitherium_ recalls the pelvis of the Rorqual. There
is a single triradiate bone with an acetabular cavity for the rudiment of
the femur in the centre; it suggests that here the three normal elements of
the pelvis have become fused into a single bone. In the Dugong there are
two small bones on each side.
The Manatees (_Manatus_)[225] are found in the fresh-waters and along the
Atlantic coasts of South America and Africa. It appears that there are four
species, of which one only is African, the others American. Report asserts
the former occurrence of this genus on the shores of St. Helena.
The Manatee is provided with only six cervical vertebrae, a fact which
distinguishes it from the other existing genera of its group. A remarkable
feature which it exhibits is the large number of molar teeth. These
apparently go on increasing indefinitely during its life, the suggestion
being that they are worn away by the nature of the food--algae with much
sand intermixed. As many as twenty molar teeth have been counted in one
half of the jaw, and there is no reason to forbid the assumption that they
{336} may get still more numerous. This large number of grinding teeth is
obviously suggestive of the Whales, with which the Sirenia are believed by
some to be allied. It is at least a remarkable coincidence that these two
aquatic groups of mammals should both have assumed the same indefinite
tooth formula. It is correct to say assumed, since extinct forms of
Manatees, such as _Halitherium_ and _Prorastoma_, have not a continuous
succession of molars. The brain of the Manatee is, contrary to the usual
arrangement among aquatic mammals, smooth, and only marked by one or two
fissures.
The Manatee[226] is black in colour, its thick skin being wrinkled. The
animal is assisted in feeding by a curious mechanism of the upper lip; this
is split in two, and the two halves, which are furnished with strong
bristles, can play upon each other like the points of a pair of forceps.
The flippers are furnished with nails, save in _M. inunguis_, but in the
nailed forms it is not every finger which is thus armed.
[Illustration]
FIG. 179.--Skeleton of Dugong. _Halicore australis._ (After de Blainville.)
_Halicore_,[227] the Dugong, is an entirely Oriental and Australian {337}
form; there appears to be but a single species, though more than one name
has been given to supposed distinct species. As already mentioned, it
differs from the Manatee in the possession of a Whale-like tail; the
nostrils, too, are more upon the upper surface of the head, and there are
no nails upon the flipper. The peculiar cleft lip of the Manatee is not so
well developed in the Dugong, but there are traces of it; and in the foetus
the likeness to the Manatee in this respect is very striking. It would thus
appear that _Halicore_ is a stage in advance upon _Manatus_; that the
remarkable mechanism of the lip of the latter has been possessed, but has
been lost, by the Dugong. The skull of the Dugong is distinguished by the
stout premaxillary bones, which bear a tusk in the male. In the female the
tooth is there, but is lodged within the bone. This incisor has a milk
forerunner. The back teeth of the Dugong (there are no canines) are few in
number (four or five, even six), thus showing a gradual reduction when
compared with _Manatus_; and this culminates in the toothless _Rhytina_. It
is also interesting to notice that in the massive lower jaw there are
traces of an incisor. Were this to be developed into a tusk, the jaw would
present a curious resemblance to that of _Dinotherium_.
The Dugong, _H. dugong_, has the reputation of being the original of the
mermaid legends, since the young is held to the pectorally-situated breast
with one flipper. "But it should be remembered," justly observes Dr.
Blanford, "that stories of beings half man or woman, half fish, are as
common in temperate as in tropical seas, and that some of them are more
ancient than any European knowledge of the Dugong."
EXTINCT SIRENIANS.--The earliest genus that can be with certainty referred
to this order is the Oligocene _Prorastoma_. This genus, though offering no
particular skull-characters that assist in the determination of the
much-debated affinities of the Sirenia, shows a remarkable condition of the
teeth that may afford a clue. The species _P. veronense_, recently
described by Mr. Lydekker,[228] is founded upon a fragment of the skull
which contains two teeth apparently representing the third and fourth upper
milk molars. The interest attaching to these teeth lies in the fact that
they clearly exhibit the buno-selenodont condition characteristic of
certain early Artiodactyles, e.g. _Merycopotamus_.
_Halitherium_ is a later genus, which is known by the nearly {338} complete
skeleton. The skull is like that of other Sirenia, with the down-turned
premaxillary region. But the nasal bones, lost, or at least rudimentary, in
recent forms, are well developed; the likeness of ancient to living forms
in this respect being exactly paralleled by the Zeuglodonts, when compared
with recent Whales. The vertebral centra exhibit distinct epiphyses, which
have disappeared in living Sirenians. The cervical vertebrae are seven, of
which the second and third are occasionally fused. There are nineteen pairs
of ribs, and there are three lumbar vertebrae. The sternum consists of
three separate pieces. There is a rudimentary femur.
The recently-extinct Steller's Sea-cow, belonging to the genus _Rhytina_,
was a huge beast, seen in the flesh up to nearly the end of the last
century. It frequented the shores of Bering's Straits. Its remains occur in
the peat on the shores of those seas. It reaches a length of some 20 to 30
feet. The external characters were much like those of other recent
Sirenians. The nostrils were above the fore part of the snout, the latter
being truncated and obtuse. The tail was of the Cetacean pattern, and thus
like that of _Halicore_. The head of this Sirenian was small, and the teeth
had entirely vanished save for the apparent existence as transitory
structures of two small incisors in the upper jaw. The absence of teeth was
compensated by the presence of a horny palate for the trituration of the
sea-weeds which constituted the food of Steller's Sea-cow. The fore-limbs
seem to have possessed no nails, but were covered at the extremity with
short, bristly hairs, no doubt serving the purpose of keeping the animal
moored in safety to the slippery beds of Fucus upon which it browsed.
There are nineteen pairs of ribs. The vertebrae of the cervical region are
the customary seven, and the centra are thin and plate-like as in the
Cetacea, the animal being thus short-necked like those marine creatures.
* * * * *
{339}
CHAPTER XII
CETACEA--WHALES AND DOLPHINS
ORDER VI. CETACEA.[229]
Aquatic Mammalia of fish-like form; tail expanded into horizontal flukes; a
fatty dorsal "fin" present in most species; anterior limbs converted into
fin-like paddles; posterior limbs only represented by skeletal rudiments.
Hairy covering reduced to a few isolated hairs in the neighbourhood of the
muzzle. Nostrils represented by the single or double blow-hole, nearly
always situated far back upon the skull. Bones of loose texture and much
impregnated with oil. The skull has a greatly-developed facial portion;
supra-occipital bones meeting the frontal by overgrowing, or growing in
between the parietals; bones surrounding the organ of hearing loosely
attached to the skull, the tympanics of peculiar cowrie-shell form.
Coronoid process of mandible absent, or very feebly developed. Teeth, when
present, few or numerous, always of simple conical form, with at most
traces of additional cusps (_Inia_); if absent their place taken by
whalebone. Cervical vertebrae of short antero-posterior diameter, often
more or less completely welded together into a single mass. Articulations
between dorsal and other vertebrae feeble. Scapula peculiarly flattened;
acromion strongly developed as a rule, but arising from a slightly-marked
spine; coracoid process generally strongly developed. Phalanges of digits
always more numerous than in other mammals. Clavicles absent. Stomach
complex, consisting of at least four and often more chambers. Lungs simple
and non-lobulated. Diaphragm obliquely set and very {340} muscular. Brain
much expanded transversely and well convoluted. Testes abdominal. Teats
two, inguinal in position. Placenta diffuse and non-deciduate.
The Whales and Dolphins, which constitute this order, form an assemblage
which is easily characterised by reason of the fact that their affinities
to other groups of Mammalia are so doubtful that they furnish matter rather
for speculation than for authoritative statement. Some hold that they
resemble in certain points the Ungulata; while others again see in them the
culminating term of a series which commences with such a form as the Otter,
and of which the Seals and Sea-lions are intermediate stages. A third
opinion is that the Whales have arisen from some low mammalian stock, too
primitive to be assigned to any existing order of mammals. Palaeontology,
as will be seen later, throws no light whatever upon their origin. This
matter has already been referred to (see p. 120) in considering the
position of the Cetacea.
The Whales include the most gigantic of all the orders of vertebrated
animals. No creature living or extinct is so large as the Sibbald's
Rorqual, which attains to a length of some 85 feet, or perhaps even rather
more. On the other hand we have what are by comparison minute forms. Apart
from the possibly problematical _Delphinus minutus_, stated to be only 2
feet in length, we have as a minimum 3 or 4 feet. The size of the Cetacea
has been subjected to much exaggeration. The first duty of a Whale,
observed the late Sir William Flower, is to be large; and Natural
Historians, in the recent as well as in the remote past, have not hesitated
to put very round numbers upon the dimensions of the larger members of the
order. We may perhaps pass over Pliny's "fish called balaena or whirlpool,
which is so long and broad as to take up more in length and breadth than
two acres of ground," and a number of analogous exaggerations, which
gradually dwindled down to the dimensions just stated of the great Rorqual.
M. Pouchet has made the ingenious suggestion that the statements of the
ancients may have been nearer the truth than observations of to-day would
have us believe; he pointed out justly that in former times Whales were not
so relentlessly pursued as during the last century; the inference being
that they may have lived to a greater age, and attained a more colossal
bulk. The more modern exaggerations in the {341} dimensions of the bigger
Whales are probably due to the fact that measurements have been taken, not
in a straight line from snout to tail, but along the bulging sides of the
Cetacean, rendered even more convex than in nature by decomposition, and by
pressure due to the immense tonnage of the creature.
The Cetacea are the most perfectly aquatic of all mammals; they never leave
the waters which they inhabit. It is true that legends have represented
them as pasturing upon the shore--Aelian spoke of Dolphins basking in the
sun's rays upon the sand; and the "Devil Fish" of California,
_Rhachianectes_ (see p. 357) has given rise to improbable stories--but they
are apparently only legends. Indeed a stranded Whale cannot live long, for
it is unable to breathe, the comparatively feeble breast being crushed by
its own weight. In accordance with the purely aquatic habit, we find a
modification of the outward form of the body (and as we shall see later of
many of the internal organs), which renders the Cetacea externally unlike
all other mammals. The form is fish-like, the fore-limbs are paddles, the
tail is expanded into two horizontal flukes, which serve to propel the
creature through the water.
[Illustration]
FIG. 180.--Killer. _Orca gladiator._ x 1/40 (After True.)
The skin is smooth and shiny, so smooth and so shiny that it has often been
compared to coach leather. But nevertheless they are not entirely without
that most essential character of the class Mammalia, a coating of hair. The
hairy covering is, however, reduced to the very smallest proportions; it is
represented {342} by a few hairs only--so few that they can be counted with
ease--in the neighbourhood of the muzzle. These hairs are not present in
all Whales; they are absent, for example, in the White Whale or Beluga.
When present they are not furnished either with sebaceous glands or with
muscular fibres, which are such universal concomitants of the hair
follicles in the Mammalia generally. This appears to be conclusive evidence
that the hairs, few as they are, are still undergoing degeneration. The
need for a furry coat is removed by the presence of a thick coating of fat
immediately underlying the skin. This is known as the blubber, and is the
main incentive to the pursuit of Whales. It must not, however, be assumed
without further argument that the hair is absent because its place is
taken, as a mechanism for retaining the heat, by the blubber; for the Seal
tribe possess both fur and blubber. Another conceivable explanation is
quite at variance with such a view of economy. It may be noticed that among
Ungulates there is a tendency to lose hair, particularly among more or less
aquatic forms. Thus the Hippopotamus is almost naked (as is indeed the
Walrus); the Rhinoceros, too, often a frequenter of marshy soil, is almost
as denuded as is the Hippopotamus. It is not, however, settled that the
Whales have anything to do with the Ungulata; otherwise an additional
argument might be used, that is, the secular loss of hair in some members
of this group. The Hairy Rhinoceros, _Rh. tichorhinus_, was, as its name
denotes, a hairy beast; the Mammoth was equally so. The descendants, or at
least the modern representatives of both these creatures, are but scantily
clad with hairs.
A final reason for the naked character of the skin in existing Cetacea is
closely connected with a feature in the organisation of three or four
living species which must first be described.
Some years ago the late Dr. J. E. Gray of the British Museum described from
the sea, off Margate, what he considered to be a new species of Porpoise,
characterised by the presence on the dorsal fin of a row of stony
tubercles. As a matter of fact it was subsequently shown that the Common
Porpoise has the same structures, so that there was no need for a Margate
species, _Phocaena tuberculifera_. Moreover, in the Indian _Neomeris_, a
close ally of the Porpoise, a more abundant calcified covering of scales
exists along the whole back of the animal. These plates, {343} it has been
discovered, are larger in the foetus, a fact which naturally points to
their being an inheritance from the past, now undergoing retrogressive
changes. Such a way of looking upon the facts is confirmed by the finding,
many years ago, by the naturalist and physiologist Johannes Mueller, of
bony plates in connexion with the remains of a Zeuglodont Cetacean. It
looks, therefore, very much as if the Eocene ancestors of the modern
Cetacea had a skin studded with bony plates, as have the armadillos. This
being the case, the disappearance of hair is not surprising. The room would
be taken up by the calcified plates, and when the latter disappeared, as
they have in the vast majority of existing Whales, the naked skin alone
would be left.
Whales possess no externally-visible hind-limbs; rudiments of these
appendages are present, which will be dealt with under the description of
the principal features of the skeleton. But it has been discovered that in
the Porpoise, external vestiges of hind-limbs do appear in the foetus, a
fact which, be it observed, does away with the old view that the flukes of
the Whale are the last term in the series of vanishing hind-limbs, of which
the Seals, with their hind-limbs and tail bound up together, offer an
intermediate step.
The tail is fish-like in form, but the flukes are horizontal instead of
vertical as in fishes and _Ichthyosaurus_. This arrangement is no doubt
associated with the need for rapid return to the surface waters after a
prolonged immersion in search of food. A downward stroke, such as is given
by the powerful and large tail flukes, would naturally bring about this
result rapidly. The tail, moreover, is under all circumstances the swimming
organ. Its motion has been stated to be slightly rotatory, like that of a
screw, and it is the case that the two flukes are often alternate in shape
like the flanges of a screw; one being convex upwards, the other convex
downwards.
The fore-limbs are in the form of paddles, but they do not apparently serve
as organs of locomotion so much as balancers. When a Whale is killed, it
falls over on to one side, the office of the flippers being to maintain the
proper position. It is believed, however, from the fact that the embryo
often shows a relatively larger pectoral fin than that of the adult--the
difference being due to a reduction in the adult of the number of
phalanges--that the fin was once an organ of progression. {344}
The pectoral fin of Whales exists in two forms. In the Toothed Whales it is
shorter and rounder; in the Whalebone Whales longer and narrower.
Structural differences accompany these outward dissimilarities. In the
first-named group the humerus and the beginning of the radius and ulna are
within the body, and do not form a part of the fin. In the Whalebone
Whales, on the other hand, the fin contains all the bones of the fore-limb.
Another remarkable contrast between the hand in the two groups of Whales is
that while the Toothed Whales have five fingers, thus justifying the
prevailing opinion that they are the more primitive of the two groups, the
Whalebone Whales have only four fingers. Actually the Right Whale,
_Balaena_, seems to have five fingers; and, indeed, the fact that it has,
is often used to distinguish it from the Humpback, which has undoubtedly
only four. But a careful consideration of the state of affairs which
prevails in the foetus of _Balaenoptera_ dispels this idea. Between what
are apparently the second and third fingers, a rudimentary finger,
consisting of four phalanges, appears. This is not produced, as is an
additional finger found in the White Whale or Beluga, by a splitting of a
finger. Accordingly the four-fingered condition of the Whalebone Whales is
produced by the dropping out of a finger in the middle of the series,--a
very remarkable fact. When fingers disappear, as, for instance, in the
Horse, etc., it is at the two ends of the series that the digits vanish. If
this view of Professor Kuekenthal's[230] be accepted, it follows that the
presumed thumb of the Right Whale is what has been termed the prepollex.
The hand of the Whales, like those of some other aquatic creatures, _e.g._
the reptile _Ichthyosaurus_, has a larger number of phalanges than have
terrestrial animals. The result of this is, of course, to increase the
length of the fin and its utility as a paddle. It is commonly not all the
fingers that have developed this great number of accessory phalanges.
Rudimentary nails have been found upon the Cetacean hand; but in no case
are they functionally developed. In the Manatees we have the disappearance
of the nails still imperfectly accomplished. In _M. latirostris_ there are
nails; these have vanished, apart from possible traces to be seen with a
microscope, in _M. inunguis_.
A very characteristic feature of certain Whales are the furrows {345} to be
seen on the throat. This is especially the case with the Rorquals, in which
group the Humpback Whale, _Megaptera_, is to be included. The whales of
these two genera (_Balaenoptera_ and _Megaptera_) have a large number of
the throat furrows--as many as sixty have been counted. Some other Whales
have a smaller number; thus _Rhachianectes_ has but two on each side, and
the Physeteridae have not many more. These furrows are absent in very young
embryos. It is thought by Professor Kuekenthal that they allow of a wide
opening of the mouth.
[Illustration]
FIG. 181.--Dorsal surface of bones of right anterior limb of Round-headed
Dolphin (_Globicephalus melas_). x 1/10. The shaded portions of the digits
are cartilaginous. _c_, Cuneiform; _H_, humerus; _l_, lunar; _R_, radius;
_s_, scaphoid; _td_, trapezoid or magnum; _U_, ulna; _u_, unciform; _II-V_,
digits. (From Flower's _Osteology_.)
The blow-hole of Whales is, of course, the aperture of the nostrils, which
are not so far back in the foetus as in the adult. By the characters of the
nostrils the Toothed Whales can be distinguished from the Baleen Whales; in
the latter the orifice is double, in the former single. In embryos of
Dolphins, however, the two apertures are quite independent. The phenomena
of spouting have often been misinterpreted.[231] When the Whale breathes,
the expired air rushes out through the nostrils. The water vapour in the
breath condenses into drops of water in the cold Arctic regions where the
phenomenon has been mainly observed. Hence the idea that water taken in at
the mouth is expelled through the blow-hole. As the Whale approaches the
surface to breathe, it may be that some of the water of the sea is {346}
driven upwards by the forcible expulsion of air from the lungs. But for the
most part the water which is spouted is simply condensed breath.
Like some, but not all, other aquatic Mammalia the Whales have apparently
no external ear. Indeed the opening of the ear is excessively small. In a
huge Rorqual it will "admit a quill"; and although "a quill" is rather
vague, we may fairly allow any sized quill without proving that the orifice
of the auditory passage is anything but exceedingly minute. As a proof,
added to so many, that the Whales are the progeny of terrestrial creatures,
we have the occasional traces of external ears.[232]
[Illustration]
FIG. 182.--Left lower jaw of foetus of _Balaenoptera rostrata_. Inner
aspect, natural size, showing teeth. (After Julin.)
Whalebone Whales never possess permanent teeth as well as the baleen; but
in the foetus are more than traces of true teeth, which, however, never
arrive at maturity. The whalebone itself is described later (p. 354). That
the Whalebone Whales possess teeth while in the foetal condition was
discovered so long ago as 1807. It has since been confirmed by many
observers. Not only is there one set of teeth developed in the foetal
_Balaenoptera_ but two, of which one comes to a greater maturity; the
other, in fact, remaining at a very early stage of development. The more
complete dentition belongs to the milk series, as is the case with the
Toothed Whales. A very interesting conclusion with regard to the derivation
of the simple conical teeth of Whales seems to follow from the development
of these structures in Balaenoptera. There are in the young foetus fewer
teeth than in the more advanced embryo. Now in the younger embryo some of
the teeth are furnished with more than one cusp; they are bi- or even
tri-conodont. As Sir R. Owen observed, the teeth--some of {347} them--are
literally double teeth. This is a suggestion of the more complicated teeth
of the Zeuglodonts, and shows so far that the simple conical teeth of
existing Whales (cf. however the Platanistidae) are not by any manner of
means so primitive as their actual structure would undoubtedly lead one to
believe. Further than this, the greater number of teeth in the older embryo
coincided with the disappearance of these double teeth, which seem to split
up into the simple conical teeth.
The Toothed Whales are not furnished with baleen, but with teeth only.
These teeth are more or less numerous, their arrangement being of value in
the classification of the group; a matter which is dealt with later.
In the Narwhal, whose dentition in the adult is reduced to the well-known
tusk or tusks (properly developed only in the male), there is a complete
foetal dentition. A very curious fact has been elucidated by Professor
Kuekenthal about the dentition of the Common Porpoise. It appears that in
this Cetacean the two teeth corresponding to each other of the two
dentitions may fuse into a single tooth, which has in consequence a double
crown. It may be that this is the case with the Platanistid _Inia_, and
that its diconodont teeth are not, therefore, a reminiscence of the
comparatively complicated teeth of the ancient Zeuglodonts.
The internal organs of Whales which show the greatest peculiarities as
compared with other mammals are the stomach, the lungs, and the diaphragm.
Whales always possess a complicated stomach divided into many, but into a
variable number of, chambers: there are as few as four in some, as many as
fourteen in Ziphioids.
On account of its complication the stomach[233] has been compared to that
of Ruminants--it has even been alleged that Whales "ruminate"--but the
comparison will not hold good. Nor, on the other hand, is there a very
close resemblance to the equally-complicated stomach of the Sirenians.
The Rorqual has a stomach with as few compartments as any. The only Whale
which appears to have fewer is _Balaena mysticetus_, where there are but
three. In the Rorqual the oesophagus opens into a more or less globular
sac; from the upper end of this, _i.e._ close to the entry of the
oesophagus, arises the second chamber, long and narrowish; then follows an
extremely short third sac, {348} then a larger fourth, after which comes
the dilated commencement of the small intestine. The latter might be
regarded as a chamber of the stomach were it not for the fact that the
ducts of the liver and the pancreas open into it. This represents one type
of the Cetacean stomach, which seems to be found in all Whales except the
Ziphioids. In the latter, the oesophagus opens into the first compartment
as usual; but the second division of the stomach arises not close to the
entrance of the oesophagus, but at the opposite end. It would seem,
therefore, as if the first division of the stomach, found in most Whales,
were missing in Ziphioids. This way of looking at the matter is confirmed
by the fact that in _Hyperoodon_ a remnant of the missing first stomach is
found in the shape of a small diverticulum of the oesophagus just before it
enters the stomach.
The essential difference between the Whale's and the Ruminant's stomach is
this: in the latter the stomach is primarily divided into two portions, of
which the first is non-digestive and is clothed with oesophageal
epithelium. The second, the abomasum, is the digestive region. The first
part is again divided into three compartments. In the Whales, on the other
hand, it is the digestive part which is again subdivided, while if the
first part is divided it is not markedly so as in the Ruminants.
The lungs are remarkable for their unlobulated character; in this they
agree with the lungs of the Sirenia. The thoracic cavity in which they lie
is barrel-shaped, and not, as is usual in terrestrial mammals, boat-shaped,
_i.e._ narrower sternally than above. The alteration of the shape of the
thoracic cavity is associated with the aquatic life; so at any rate the
fact that it is also marked in Seals and even in the Otter seems to show.
The Whales are also characterised by the great obliquity of the diaphragm,
which is extremely muscular. In this character again we find an agreement
with the Sirenia, and also with other aquatic mammals; it is not therefore
a character of Whales so much as evidence of an adaptation to the aquatic
life. The advantage is, it appears, in the increased capacity of the
thoracic cavity, and the consequent greater possibilities of expansion of
the lungs, which it must be remembered serve as hydrostatic as well as
breathing organs.
Some of the internal arteries of Whales break up into retia mirabilia.
Their kidneys are lobulated; whether this has {349} anything to do with the
aquatic life is not so clear. It also characterises the Sirenia, more or
less, and the Otters; but, on the other hand, the terrestrial Bears show
the same structure as do also some Ungulates. It must be borne in mind,
too, that the kidneys of foetal Man are lobulated.
The liver is a compact organ not showing such lobulation as is common, but
not universal, among mammals.
The bones of Whales have a somewhat loose structure, and are much
impregnated with oil. In many features the skeleton of Whales is highly
distinctive of the order.
[Illustration]
FIG. 183.--Skeleton of Porpoise (_Phocoena communis_), _acr_, Acromion
process of scapula; _cerv_, united cervical vertebrae; _chev_, chevron
bones; _cor_, coracoid process; _hu_, humerus; _hy_, hyoid; _jug_, jugal;
_lumb.trans_, lumbar transverse processes; _max_, maxilla; _nas_, nasal;
_orb_, orbit; _par_, parietal; _pelv_, vestige of pelvis; _per.ot_,
periotic; _pr.max_, premaxilla; _rad_, radius; _rb_^1, first rib;
_rb^{12}_, twelfth rib; _sc_, scapula; _s.occ_, supra-occipital; _st_,
sternum; _uln_, ulna; _zyg_, prezygapophysis. (From Parker and Haswell's
_Zoology_.)
[Illustration]
FIG. 184.--Under surface of the cranium of a young Caa'ing Whale
(_Globicephalus melas_). x 1/5. _AS_, Alisphenoid; _BO_, basioccipital;
_cf_, condylar foramen; _ExO_, exoccipital; _Fr_, supra-orbital process of
frontal; _gf_, glenoid fossa of squamosal; _Ma_, body of malar; _Mx_,
maxilla; _OS_, orbitosphenoid; _Per_, posterior (mastoid) process of
periotic; _Pl_, palatine; _PMx_, premaxilla; _Pt_, pterygoid; _Sq_,
squamosal; _tg_, deep groove on squamosal for meatus auditorius externus,
leading to tympanic cavity; _Ty_, tympanic; _Vo_, vomer; _ZM_, zygomatic
process of malar. (From Flower's _Osteology_.)
The brain case is small proportionately and rounded. The "face" is
therefore long, and in some cases, especially among the fossil forms of
Platanistidae, the rostrum is extraordinarily elongated. The asymmetry of
the Whale's skull is one of its most remarkable features; this, however, is
entirely limited to the Toothed Whales, and among them is more pronounced
in some forms than in others. Thus the Platanistidae and many Ziphioids are
not nearly so asymmetrical as the {350} Dolphins and, especially,
_Physeter_. This asymmetry affects particularly the premaxillae, the
maxillae, and the nasals. The base of the skull is symmetrical. The Whale's
skull has very long premaxillae which, however, do not, except in the
extinct Zeuglodonts, bear any teeth. The nasal bones, whether symmetrical
or the reverse, are very small in existing Whales, which arrangement,
together with the long and broad maxillary bones, removes the anterior
nostrils, the blow-hole, far backwards. The roof of the skull is not at all
formed by the parietals externally. These bones form a portion of the side
of the cranium, but are replaced or covered by the {351}
enormously-developed supra-occipital in the adult. Here again the
Zeuglodonts are more typically Mammalian, for in them the parietals have a
normal development and situation, rising even into a median crest as in so
many quadrupeds. The bones related to the organ of hearing, the tympanis
and petrous bones, are very solid and dense in structure. Moreover they are
but loosely attached to surrounding bones, and are thus easily and
frequently lost. Nearly the only mammals which resemble the Whales in the
fact that the pterygoids sometimes meet in the middle line below are the
Edentata (Anteater and Armadillo, see p. 167). But in both groups this
peculiarity is not universal.
[Illustration]
FIG. 185.--A section of a skull of a young Caa'ing Whale (_Globicephalus
melas_). x 1/5. _a_, Angle; _an_, anterior nares; _AS_, alisphenoid; _bh_,
basihyal; _BO_, basioccipital; _BS_, basispnenoid; _cd_, condyle; _cp_,
coronoid process; _ExO_, exoccipital; _Fr_, frontal; _id_, inferior dental
canal; _IP_, interparietal; _ME_, ossified portion of the mesethmoid; _Mx_,
maxilla; _Na_, nasal; _Pa_, parietal; _Per_, periotic; _Pl_, palatine;
_PMx_, premaxilla; _pn_, posterior nares; _PS_, presphenoid; _Pt_,
pterygoid; _s_, symphysis of mandible; _sh_, stylohyal; _SO_,
supra-occipital; _Sq_, squamosal; _th_, thyrohyal; _Vo_, vomer. (From
Flower's _Osteology_.)
The vertebral column is remarkable for the fact that more or fewer of the
cervical vertebrae may be fused together into a short and compact mass.
This is seen at its maximum in the genera _Balaena_ and _Neobalaena_. The
odontoid process of the second {352} vertebra, though hardly at all marked,
is nevertheless really present and developed from a bony centre of its own,
as in other mammals. The dorsal and lumbar vertebrae are, of course, to be
distinguished by the presence of ribs attached to the former; but as there
is only a rudimentary pelvis, not attached to the vertebral column, no
sacral region can be detected. The caudal vertebrae are to be recognised by
the [234]-shaped chevron bones below.
[Illustration]
FIG. 186.--Section through middle line of united cervical vertebrae of
Greenland Right Whale (_Balaena mysticetus_). x 1/9. _a_, Articular surface
for occipital condyle; _e_, epiphysis on posterior end of body of seventh
cervical vertebra; _sn_, foramen in arch of atlas for first spinal nerve;
1, arch of atlas; 2, 3, 4, 5, 6, conjoined arches of the axis and four
following vertebrae; 7, arch of seventh vertebra. (From Flower's
_Osteology_.)
[Illustration]
FIG. 187.--A, Sternum of Greenland Right Whale (_Balaena mysticetus_). x
1/15. B, Sternum of Common Rorqual or Fin Whale (_Balaenoptera musculus_).
x 1/10. (From Flower's _Osteology_.)
The sternum in the Whale tribe is much more modified in the Whalebone
Whales than in the Odontocetes. In the latter it is made up of several
pieces, as in other mammals, which often, however, become coalesced. In the
Mystacoceti this bone is a single piece, to which only one pair of ribs is
attached, and its {353} form is characteristic of the genus. It is
heart-shaped, more or less, in _Balaena_, and somewhat cross- or
[235]-shaped in the genus _Balaenoptera_. In the Odontocetes the ribs have,
some of them, the normal attachment by capitulum and tuberculum. In the
Mystacocetes the attachment, where it exists, is very loose, and the
tuberculum alone is attached to its vertebra. This allows of the freer play
of the ribs during respiration. The scapula has a very characteristic form
in these animals. The acromion, where it exists, is placed near the
anterior margin of the shoulder blade, and overlaps the generally long
coracoid process. Clavicles are totally absent. The pelvis is very
rudimentary, consisting merely of a single bonelet, to which are attached
the rudiments (in some cases) of a femur, and, in _Balaena_ (Fig. 188), of
a tibia also.
[Illustration]
FIG. 188.--Side view of bones of posterior extremity of Greenland Right
Whale (_Balaena mysticetus_). x 1/8. _i_, Ischium; _f_, femur; _t_,
accessory ossicle representing the tibia. (After Eschricht and Reinhardt)
(from Flower's _Osteology_.)
Whales are to be divided into three great groups:--(1) the Whalebone Whales
or Mystacoceti; (2) the Toothed Whales or Odontoceti; and (3) the
entirely-extinct Archaeoceti or Zeuglodonts.
SUB-ORDER 1. MYSTACOCETI.
This division is thus characterised:--Teeth are never functionally
developed; they are present in the young, but replaced in the adult by the
baleen or whalebone; the external respiratory aperture is double; the skull
is perfectly symmetrical; the rami of the mandible are arched outwards and
do not form a true symphysis; the sternum is always composed of a single
piece of bone; the ribs articulate only with the transverse processes of
the vertebrae.
The Mystacoceti are nearly invariably huge creatures, the sole exceptions
being the Pygmy Right Whale, _Neobalaena_, and {354} a small Rorqual. But
even these are larger than the majority of Toothed Whales.
The most characteristic feature by which the Whalebone Whales are to be
distinguished from other Whales is that which gives to them their name, the
presence of whalebone. Whalebone is a horny product of the epithelium
lining the mouth, and is comparable to an exaggeration of the transverse
ridges which are found in the mouths of all mammals upon the palate. In
non-Cetacean mammals these ridges vary in depth, and are arranged as a rule
transversely, but with an oblique inclination. This is precisely how the
plates of baleen are disposed in the mouth of a Whale. Each piece of "bone"
is triangular in shape, the broader end being that of attachment while it
narrows gradually; the inner side of the blades is frayed out into a number
of threads which form the straining apparatus. The plates vary in length up
to as great an extreme length as 13 feet, which occurs in the Right Whale
at times. The colour is black or paler, even white. The number of these
plates in the mouth is very great. As many as 370 blades have been counted.
They diminish in length towards both ends of the series. Though whalebone
has been in use for a long period, whence the whalebone came was formerly
one of those things not generally known.
[Illustration]
FIG. 189.--Section of upper jaw, with baleen plates, of _Balaenoptera_.
_a_, Bone of jaw; _b_, gum; _c_, straight edge of baleen plate; _d_, _e_,
frayed out surface of baleen plates. (After Owen.)
A very prevalent notion was that the whalebone formed the eyelids or
perhaps the eyelashes of the creature. Scaliger, commenting upon Aristotle,
held that the whale had "lamellae upon the eyebrows, which, when the head
is plunged below the surface, were raised by the water; but when the animal
raised its head {355} above the waves the lamellae fell and covered the
eyes." Whalebone, too, has been often spoken of as "the fin of a whale,"
"the finnes that stand forth of their mouths." The value of whalebone is
still great, in spite of various substitutes which are now used in its
place. In the year 1897, for example, the value of this article was L2000
per ton. As a single Whale may produce several tons of this material, it is
not surprising to find that the results of a whaling voyage may be very
profitable.
FAM. 1. BALAENOPTERIDAE.--This genus _Balaenoptera_ includes the Rorquals,
which are Whalebone Whales of large size, differing from the Right Whales
in three important external characters: the head is comparatively small;
there is a dorsal fin; the throat is marked by numerous longitudinal
furrows. The bones of the cranium are not so arched as in the Right Whales,
and as a consequence the plates of baleen are shorter. The hand is only
four-fingered. The cervical vertebrae are for the most part all free. One
of the earliest records of a Whale stranded in the Thames was probably of a
species of this genus in the year 1658, and is thus described by John
Evelyn:--"A large whale was taken betwixt my land butting on the Thames and
Greenewich, which drew an infinite concourse to see it, by water, horse,
coach, and on foot, from London and all parts.... It was killed with a
harping yron, struck in the head, out of which spouted blood and water by
two tunnells, and after an horrid grone it ran quite on shore and died. Its
length was 58 foot, heighth 16; black skinn'd like coach leather, very
small eyes, greate taile, onely two small finns, a picked snout, and a
mouth so wide that divers men might have stood upright in it; no teeth, but
suck'd slime onely as thro' a grate of that bone which we call whalebone,
the throate yet so narrow as would not have admitted the least of fishes
... all of it prodigious, but in nothing more wonderful that an animal of
so greate a bulk should be nourished onely by slime thro' those grates."
Professor Collett has recently given[236] an elaborate account of the
characters and habits of this great Whale (_Balaenoptera musculus_). Though
a large beast (44 to 67 feet in length) it is exceeded by other Rorquals;
it is of a dark grey blue colour above, white, for the most part, below.
The dorsal fin is large and high; the flippers relatively slender and
small. The whole throat from the {356} symphysis of the jaws to the middle
of the belly is, as in other species, marked by furrows, forty to
fifty-eight in number. The hairy covering is reduced (in an adult female)
to thirteen hairs on each side of the lower jaw; in a foetus there were
also seven hairs on each side of the upper jaw, as well as rather more on
the lower jaw--altogether, forty-eight. This Whale appears to feed chiefly
upon small Crustacea, especially the Copepod, _Calanus finmarchicus_. The
number of baleen plates is about 330 on each side of the jaw. This Whale
sometimes swims singly, but usually in schools of even as many as fifty.
Rudolphi's Rorqual (_B. borealis_) seems to be a perfectly inoffensive
beast; it is said to be able to stay under water for as long a time as
twelve hours.
A smaller species than the last is _B. rostrata_--at the outside 33 feet in
length. Here the hairy covering is reduced[237] to "two small hairs on the
integument covering the apex of the lower maxilla." The colour is greyish
black above, the underside white. On the other hand, _B. sibbaldii_, the
Blue Whale, is the giant of its race, reaching a length of 85 feet. Its
colour is a dark bluish grey, with small whitish spots on the breast. The
dorsal fin is small and low with straight margins.
_B. musculus_, the Finner, is intermediate in size--not more than 70 feet.
It seems doubtful whether the "sulphur bottom," _B. australis_, of
Antarctica and _B. patachonica_ differ specifically from this.[238]
The genus _Megaptera_ is very near _Balaenoptera_, but differs from it
mainly in the following external and internal characters. The dorsal fin is
not very prominent, and its place is taken by a lowish hump, whence,
indeed, the common name of this Whale, "Humpback." The pectoral fin is
unusually long, and the creature uses it to beat itself, the surrounding
water, and, more playfully, its mates. The general outline of this Cetacean
is more clumsy than that of _Balaenoptera_. The most important internal
difference is in the form of the scapula, which has at most a slight
acromion and coracoid process. These are rather more pronounced, according
to Messrs. van Beneden and Gervais,[239] {357} in the southern form of the
genus, which is known as _M. lalandii_. The head, it should also be
remarked, is studded with large tubercles about the size of an orange,
which seem to be hyper-trophied rudiments of the hairs, which should be
present in this region of the body. As is the case with other Whales,
numerous species have been made out of individuals of _Megaptera_. Captain
Scammon, who observed many "gams" or herds of these Whales, remarked[240]
that he had extreme difficulty in finding any two individuals precisely
alike! The best-known species in any case is the northern _M. longimana_,
which occurs on our own coasts. The genus is, like so many Cetaceans,
world-wide in range; and it is possible that the difference in the scapula
already referred to may justify the separation of a southern _M. lalandii_
(with which in that case, perhaps, _M. capensis_ and _M. novae zelandiae_
will be synonymous). Quite recently M. Gervais has insisted upon a
_Megaptera indica_ from the Persian Gulf. _Megaptera_ grows to a length of
50 to 60 feet. Seventy-five feet have been stated, but measurements of
Whales have usually to be received with caution.
_Rhachianectes_, with but one species, _R. glaucus_,[241] the "Californian
Grey Whale," is the last genus of the family Balaenopteridae. This Whale is
but imperfectly known anatomically; but quite sufficient has been
ascertained to show its great divergence from _Balaenoptera_ or
_Megaptera_. The dorsal fin is completely absent, and the throat pleats, so
characteristic of the typical Balaenopteridae, are reduced to two. It has,
however, the general outline of a Rorqual, with a relatively small head. In
osteological characters it tends to unite the two families Balaenopteridae
and Balaenidae (if they are really necessary subdivisions). The skull is on
the whole Rorqual-like; but its fore-part is narrow as in the Greenland
Whale, and the premaxillaries are pinched up in the middle line so as to be
visible from the side; this again is a Balaenid character. The cervical
vertebrae are free as in Rorquals, and the sternum is quite as in that
group. The scapula has more the shape of that of _Balaena_.
_Rhachianectes glaucus_ is confined to the Pacific, and has been
extensively hunted from the shore. It is not, however, a very valuable
Whale, since the baleen is short as in Rorquals, and the {358} beast,
moreover, appears to be fierce, a somewhat rare attribute of Whales. It has
been spoken of, indeed, as "a cunning, courageous, and vicious" animal.
_Rhachianectes_ is essentially a coast Whale, and loves to lie in the surf
in quite shallow water waiting for the tide to float it off. This Whale
varies much in colour from black to mottled grey and black, and reaches a
length of about 40 feet.
FAM. 2. BALAENIDAE.--The Right Whales of the genus _Balaena_ are to be
distinguished from _Neobalaena_ and from the Rorquals by the following
characters:--
The size is large, 50 to 60 feet. There is no dorsal fin. The head is more
than or nearly one-fourth of the entire length of the animal. The baleen is
very long. The throat is not grooved. The orbital process of the frontal is
not wider than the downward process of the maxilla. The cervical vertebrae
are all fused. The scapula is rather high. The hind-limb has the rudiment
of a tibia. The intestine has no caecum.
A vast number of different genera have been founded on detached bones, bits
of whalebone, and more or less complete skeletons of Right Whales coming
from different parts of the world. In Dr. Gray's catalogues we find the
following allowed, viz. _Balaena_, _Eubalaena_, _Hunterius_, _Caperea_,
_Macleayius_. The number of "species" distributed among the genera is some
thirteen or more, with whose names we shall not trouble the reader. As a
matter of fact there are not more than two species which can with certainty
be identified and distinguished, both of which are so close that they
cannot possibly be placed but in the same genus, _Balaena_. In no group of
Whales--in no group of animals probably--has imagination run riot to so
terrible an extent in the formation of genera and species as in these Right
Whales. This multiplication or rather division of genera has arisen from an
old idea that Whales coming from different seas must be of different kinds,
a notion now thoroughly exploded.
The term "Right Whale" simply means that the Whales of this genus are the
right kind of Whale for the whaler to pursue. Their whalebone is longer and
more valuable, while the oil is not only more abundant but of a superior
quality. The two species demand a separate account.
The Greenland Whale, _Balaena mysticetus_, is one of the rare instances of
a Whale which has an exceedingly limited range in {359} space. It is
absolutely confined to the Arctic Ocean, and reported occurrences on our
coasts are due to a confusion with _B. australis_, to be presently
described. At the "Devil's Dyke," near Brighton, there is, or was, the
skull of a most flagrant Rorqual, which is carefully labelled "Greenland
Whale." This Whale grows to a length of 50, 60, rarely 70 feet. It is black
in colour, save for a white patch on the under side of the jaw. The head is
quite one-third of the body in length. There are a few scattered hairs at
the extremity of the jaws. The length of time which this Whale can endure
immersion has been variously stated. The utmost limit of endurance is
stated by Scammon to be one hour and twenty minutes. The pursuit of this
Whale is attended by dangers, not in the least because the animal is itself
fierce and ready to attack, but simply on account of the velocity with
which, and the great depth to which, it will dive, and also to the huge
muscular force which is exerted in its struggles to free itself from the
harpoons. It is indeed an extremely timid beast. It has been remarked that
"a bird alighting upon its back sometimes sets it off in great agitation
and terror." Combined with this timidity of disposition is an intense
affection for its young, "which would do honour," observed Scoresby, "to
the superior intelligence of human beings." Yet that trader and observer
goes on to remark that "the value of the prize ... cannot be sacrificed to
feelings of compassion"! The fact that this Whale and its congener, _B.
australis_, feed among swarms of minute pelagic creatures, which they
engulf in their huge mouths, led the ancients to believe and assert that
they fed upon water only. When the Whale feeds it moves along with some
velocity, taking in huge mouthfuls of sea water with the contained
organisms, which are then strained off by the whalebone and left stranded
upon the tongue.
Unlike its congener, the southern Right Whale, _B. australis_,[242] is
world-wide in distribution, avoiding only the Arctic regions. Where the
Greenland Whale is found _B. australis_ does not exist. The principal
differences which it shows from _B. mysticetus_ are firstly in the
relatively shorter head and shorter and coarser whalebone. In the second
place it has more ribs, fifteen pairs as against thirteen; but there is
apparently some little confusion in the matter of ribs. An additional rib
at the end of the series {360} is apt to get lost, and in the skeleton of
so huge and unmanageable a beast there is nothing more unwise than to
insist upon, as specific characters, what may be due merely to defective
preparation. This Whale has often, and the Greenland Whale also, a rough
horny protuberance upon the snout known as the "bonnet." The causation of
this is not clear. It has been spoken of as "a rudimentary frontal horn."
But this suggestion of an Ungulate affinity can hardly be accepted. It
seems to be more like a kind of corn.
This Whale was once more abundant on the coasts of Europe than it is
to-day; it was much hunted by the Basques in past time. The Whale which
frequented the Bay of Biscay was usually called the Biscayan Whale or _B.
biscayensis_; but there is probably no specific difference. Among the small
towns which fringe the Bay, it is very common to find the Whale
incorporated into the armorial bearings. "Over the portal of the first old
house in the steep street of Guetaria," writes Sir Clements Markham,[243]
"there is a shield of arms consisting of Whales amid waves of the sea. At
Motrico the town arms consist of a Whale in the sea harpooned, and with a
boat with men holding the line." Plenty of other such examples testify to
the prevalence of the whaling industry on these adjoining coasts of Spain
and France. It appears that though the fishery began much earlier--even in
the ninth century--the first actual document relating to it dates from the
year 1150. It is in the shape of privileges granted by Sancho the Wise to
the city of San Sebastian. The trade was still very flourishing in the
sixteenth century. Rondeletius the naturalist described Bayonne as the
centre of the trade, and tells us that the flesh, especially of the tongue,
was exposed for sale as food in the markets.
M. Fischer,[244] who, as well as Sir Clements Markham, has given an
important account of the whaling industry on the Basque shores, quotes an
account of the methods pursued in the sixteenth century. It was at
Biarritz--or as Ambroise Pare, from whom Fischer quotes, spelt it,
Biaris--that the main fisheries were undertaken. The inhabitants set upon a
hill a tower from which they could see "the Balaines which pass, and
perceiving them coming partly by the loud noise they make, and {361} partly
by the water which they throw out by a conduit which they possess in the
middle of the forehead." Several boats then set out in pursuit, some of
which were reserved for men whose sole duty it was to pick out of the water
their comrades who had overbalanced themselves in their excitement. The
harpoons bore a mark by which their respective owners could recognise them,
and the carcase of the animal was shared in accordance with the numbers and
owners of the harpoons found sticking in the dead body of the Whale. At
this period the fishery was at its height. But it continued to be an
occupation along those shores until the beginning of the eighteenth
century, after which it gradually declined. The fishery of Whales began to
be carried farther afield than the shore, and for a long time the Basques
furnished expert harpooners to whaling vessels proceeding to the Arctic
seas. A curious example of the continuance of the fishery until at least
1712 is given by Sir C. Markham. In the parish records of Lequeito for that
year, it is noted that a couple were married who possessed between them all
the necessary outfit for a whaling cruise.
The genus _Neobalaena_ is interesting from more than one point of view. Its
size compared with its gigantic relatives is small, some 16 or 17 feet. The
genus bears the same kind of proportion to _Balaena_ that _Kogia_ does to
_Physeter_ among the Physeteridae. It is one of those Whales which are very
restricted in habitat; up to the present it is only known from the
Antarctic region in the neighbourhood of New Zealand and South Australia.
Structurally it is in a few points intermediate between the Right Whales
and the Rorquals. The head is proportionately (as well as, of course,
actually) not so large as in _Balaena_. There is a falcate dorsal fin; but
the head in outline is not Rorqual-like in spite of its similar
proportions. The whalebone is long. The throat is not grooved. _Neobalaena_
has forty-three vertebrae, of which the cervicals are all fused. There are
as many as seventeen or eighteen dorsal vertebrae, the largest number in
any Cetacean as far as is known. With these are articulated not eighteen
but only seventeen ribs. The first dorsal vertebra appears to be without a
rib. The ribs are very broad and flat. The body thus gets an appearance of
a Sirenian. The lumbar vertebrae are fewer than in any other Cetacean,
being only two. The scapula is more like that of the Rorquals than that of
the Right Whales; {362} that is to say, it is long and not very high. The
skull is most like that of _Balaena_, but the process of the frontal
arching over the eye is broader relatively than in _Balaena_, and thus
approaches _Balaenoptera_. Nothing is known of the viscera of this Whale.
The whalebone is white, and the animal was first described by Dr. Gray from
pieces of "bone." It is not always that so fortunate a diagnosis of
specific or generic difference has been made from a structure which
apparently offers so little aid for discrimination.
There is but a single species of the genus which is named _Neobalaena
marginata_.[245]
SUB-ORDER 2. ODONTOCETI.
The _Odontoceti_ have teeth but no whalebone; the blow-hole is single; the
skull is not symmetrical; some of the ribs are two-headed.
FAM. 1. PHYSETERIDAE.--This family of the Odontocetes may be thus
defined:--All or most of the cervical vertebrae are fused together. The
costal cartilages are not ossified. In the skull the pterygoids are thick
and meet in the middle line; the symphysis of the mandible is long. Teeth,
more or fewer, are found in both jaws, but those of the mandible are alone
functional (? exc. _Kogia_). The pectoral limb is smallish. The throat is
grooved by two or four furrows.
This family of Whales is again susceptible of division into the two
sub-families--Physeterinae or Sperm Whales and the Ziphiinae or Beaked
Whales. Professor P. J. van Beneden was strongly against any subdivision of
what is here regarded as a perfectly natural family, embracing the
Physeters and the Beaked Whales. There are, however, some reasons for the
subdivision. The Ziphiinae have a reduced series of teeth, never exceeding
two on each mandible, which contrasts with the fully-toothed mandibles of
both _Physeter_ and _Kogia_. The stomach of the Ziphioids is
extraordinarily complicated even for a Cetacean. The small head of the
latter group, which recalls in a curious way that of Mosasauroid reptiles
and some Dinosaurs, is in contrast to the {363} enormous head of the
Cachalot and the very fairly-developed skull of the "Pygmy Sperm Whale."
Both, however, furnish spermaceti, and in various osteological details come
near together. On the whole we incline towards separating the Cachalots
from the Ziphioids, and shall therefore commence with the former as being
in some respects the more primitive members of the family Physeteridae.
SUB-FAM. 1. PHYSETERINAE.--This sub-family may be thus defined:--Teeth in
lower jaw numerous. No distinct lachrymal bone. Stomach with only four
compartments (? as to _Kogia_).
Of this sub-family the best-known genus is _Physeter_, including the Sperm
Whale or Cachalot. Of other reputed species we shall speak later. The genus
is characterised in the first place by its large size--as much as 82 feet
of length have been assigned to _Physeter macrocephalus_; but Sir William
Flower thought that 55 or possibly 60 feet might be a better approximation
to the greatest length of the Cachalot. The head is enormous, a third of
the length of the body, and terminates in a massive and bluntish snout.
This is, however, not so abruptly truncated as is often represented in
figures. According to Messrs. Pouchet and Chaves,[246] it slopes forward
two metres beyond the end of the lower jaw; the mouth is thus ventral and
almost shark-like in position, as is the case also with the Pygmy Sperm
Whale, to be considered later. In connexion with this peculiar position of
the mouth, it has been asserted--Mr. F. T. Bullen figures it[247]--that the
Sperm Whale turns over upon its back to bite. The blow-hole is single, and
shaped like the sound-hole of a violin; it lies upon one side, and is not
median in position. The throat is grooved as in the Ziphioids by two
grooves. The dorsal fin is represented by a whole series of lowish humps,
decreasing in elevation from before backwards. The pectoral fins are not
large relatively speaking. The great square head is not occupied entirely
by the skull; the cavity lying above, which is of course traversed by the
tube ending in the blow-hole, is filled with the spermaceti, which is fluid
fat during the life of the animal. Spermaceti also occurs in other Whales;
and that of _Hyperoodon_, whence it has been extracted for commercial
purposes, is said to offer no differences of importance from the spermaceti
of the {364} Sperm Whale. Spermaceti as a drug appears to have been first
mentioned in the pharmacopoeias of the famous medical school of Salerno
towards the year 1100. But it was confounded with a totally distinct
substance, viz. ambergris. The confusion was also made by the famous
alchemist Albertus Magnus, and by the observant Archbishop of Upsala, Olaus
Magnus, in his work _De gentibus septentrionalibus_. It was supposed in
fact by these writers to be the liberated sperm of the Whale, hence
obviously the name. Later on, the substance in question was regarded as the
brain of the Cachalot, in fact as late as the middle of the eighteenth
century. It was Hunter and Camper who really discovered the true nature of
the substance, oil of course, in the cavities of the skull.[248] The huge
skull of _Physeter_ "is perhaps the most modified from the ordinary type"
of skull in the whole mammalian class.
The top of the skull rises into a huge crest lying transversely, and from
it slope forward two lateral crests formed from the maxillary bones; in
this great basin lies the spermaceti already referred to. The skull, as in
Toothed Whales generally, is exceedingly asymmetrical. The right
premaxillary and the left nasal bones are much larger than their fellows;
indeed the right nasal is hardly present as a separate bone. The parietal
if present is fused with the supra-occipital. The jugal is large, and is
not divided into two pieces as it is in the Ziphioids. The pterygoids meet
below for a considerable distance, as in many Dolphins, and in the Edentata
among other mammals. The symphysis of the lower jaw is very long, but the
bones do not appear to be ankylosed. The length of the symphysis recalls
that of the Gangetic Dolphin, _Platanista_.
In the vertebral column the atlas alone is free, the remaining cervicals
being fused. There are only eleven dorsal vertebrae, eight lumbars, and
twenty-four caudals. The breastbone of this Whale is a roughly-triangular
bone made up of three pieces. Four cartilaginous sternal ribs are attached
to this bone. The scapula is remarkable for the fact that it is concave on
the outer and convex on the inner surface; otherwise it is quite typically
Cetacean in form. The shortness of the pectoral limb is shown by the
phalangeal formula, which is as follows:--I 1, II 5, III 5, IV 4, V 3.
{365}
One of the reasons for the pursuit of the Sperm Whale is the desire to
obtain that extremely valuable product ambergris. This substance has long
been known; but its true nature was for centuries in dispute. In Dr.
Johnson's _Dictionary_ (so recently as the edition of 1818!) ambergris is
provided with alternative definitions; it is either the excrement of birds
washed off rocks, or honeycombs that have fallen into the sea!
An old writer asserted of ambergris that it was "not the scum or excrement
of the whale, but issues out of the root of a tree, which tree, howsoever
it stands on the land, alwaies shoots forth its roots towards the sea,
seaking the warmth of it, thereby to deliver the fattest gum that coms out
of it, which tree otherwise by its copious fatness might be burnt and
destroyed." These "explanations" were caused by the fact that ambergris is
sometimes found floating in the sea. Ambergris is, of course, a product of
the intestinal canal of the Sperm Whale; it seems to be of the nature of
cholesterin, and its place of origin was conclusively proved by finding the
beaks of cuttle-fish imbedded in it. When first extracted from the
alimentary canal it is of greasy feel and consistency; later it hardens,
and acquires its characteristic sweet earthy odour. Ambergris is used
mainly as a vehicle for scents, and is a costly substance. A piece weighing
130 lbs. was valued at L500. Though now entirely used in connexion with
perfumery, it was held by the ancients to be of great value as a specific
in certain diseases.
The Sperm Whale is chiefly a tropical animal. Examples that have been cast
up on our shores are strayed individuals. It often goes about in herds,
which seem to be composed of females. Its food is chiefly cuttle-fishes,
and it is said to have a predilection for those colossal cuttle-fishes
whose existence has until recently been doubted. Mr. Bullen has sketched a
conflict between these two giants of the deep. On the other hand it is said
that its large throat, more than big enough to swallow a man (the Whale is
credited with being that which swallowed Jonah), does not usually admit
fishes larger than Bonitos and Albacores.
The ferocity of the Cachalot has been denied and affirmed. It certainly has
great strength, for it can throw itself completely out of the water.
Captain Scammon thinks that ships which are mysteriously lost at sea, with
no obviously assignable cause, are sometimes the victims of the furious
rushes of a bull {366} Sperm Whale. Marco Polo took much the same view, but
suggested that the Whale did not deliberately attack the ship, but was
deceived by the foam following in its wake into thinking "there is
something to eat afloat, and makes a rush forward, whereby it shall often
stave in some part of the ship."[249]
Sir W. Flower and many others are of opinion that there is but one species
of Cachalot. But many names have been given to supposed other forms. The
genus itself has even been divided, and to a set of vertebrae from the
south Dr. Gray gave the perfectly superfluous name of _Meganeuron kreffti_.
The "High-finned Cachalot" rests mainly upon the suggestions of Sir Robert
Sibbald. It is supposed to have a high dorsal fin, and teeth in the upper
as well as in the lower jaw. Common though it was asserted by its describer
to be, there is not a bone, not a fragment even of a bone, alleged to
belong to _Physeter tursio_ in any museum in the world! It seems premature,
therefore, to include this mysterious creature in any list of Cetacea,
though that was done by no less a naturalist than the late Mr. Thomas Bell.
It is this creature round which most of the stories of ferocity congregate.
It is held to be the monster from which Perseus delivered Andromeda, and
which was about to devour Angelica upon the shore of Brittany. The fact of
the matter is, that the Sperm Whale, like so very many other Whales, is
world-wide in range; and those naturalists who did not believe in so wide a
distribution found themselves obliged, in order to satisfy their own views,
to create new species for those of distant localities. Hence the dozen or
so of synonyms which refer to what is to be called _Physeter
macrocephalus_.
The genus _Kogia_ (sometimes written _Cogia_), the so-called "Pygmy Sperm
Whale," is a southern form of much smaller dimensions than its gigantic
ally just described. _Kogia_ does not exceed 15 feet or so in length. It
differs from _Physeter_ also in the well-marked and falcate dorsal fin, in
its generally delphinoid form, in the short snout, and the more normal (for
a Whale) shape of the blow-hole, which is crescentic.
There are also a number of osteological characters in which the two
Physeterines differ from each other. In _Kogia_ all the cervical vertebrae
are ankylosed together; the skull is short, though equally asymmetrical;
the ribs are as many as twelve or {367} fourteen; the scapula has not the
concave face that it has in _Physeter_. The functional teeth of the lower
jaw seem to be reinforced by two on each side of the upper jaw. Moreover,
the articulation of the ribs with the vertebrae does not show the very
anomalous state of affairs that characterises _Physeter_, where the two
heads of a rib may be upon one vertebra.
While there is no doubt as to the generic distinctness of _Kogia_, there is
again the same difficulty that is met with throughout the whole of the
order in settling into how many species the genus requires dividing.
We can dismiss, as unnecessary, additional generic names (_Euphysetes_,
_Callignathus_), but there do appear to be reasons for allowing two
species, if the accounts of their osteology are to be depended upon. One of
these is _K. breviceps_, with thirteen pairs of ribs, no teeth in the upper
jaw, fourteen or fifteen on each side of the lower jaw, vertebral formula
C 7, D 13, L 9, Ca 25, and phalangeal formula I 2, II 8, III 8, IV 8, V 7.
The other will then be _K. simus_, with fourteen pairs of ribs, two teeth
in the upper jaw, nine in each ramus of the lower jaw, vertebral formula
C 7, D 14, L 5, Ca 24, and phalangeal formula I 2, II 5, III 4, IV 4, V 2.
A Californian species has been called _K. floweri_, whose teeth seem to be
particularly long and recurved. And the New Zealand _K. pottsi_ has been
held to be also a distinct form. There seems to be nothing of special
interest to record about the way of life of these Cetaceans, which are but
imperfectly known.
SUB-FAM. 2. ZIPHIINAE.--Teeth in the lower jaw not more than two on each
side. A distinct lachrymal bone. Stomach with very numerous compartments.
These Whales are all of moderate size, not exceeding 30 feet or so in
length. They have a falcate dorsal fin rather near the end of the body; the
muzzle is prolonged, hence the name often given to them of "Beaked Whales."
The throat is grooved; the blow-hole is single and median, crescentic in
form, with the concavity pointing forwards. A character possibly
differentiating the Ziphioids from other Whales is the fact that the body
ends in a rounded projection between the flukes of the tail. This has at
any rate been noted in _Mesoplodon_, _Ziphius_, and _Hyperoodon_. The
Ziphioid Whales are by no means common; indeed of _Berardius_ but four or
five specimens have ever been {368} met with. Most of them are southern in
range, and the vast stretches of desolate coast which occur in these
regions of the world account possibly for the rarity of their remains.
These Whales have done duty more than once for the "Sea Serpent." Quite
recently an alleged sea serpent turned out to be a couple of _Mesoplodon_
lying head to tail! The head in these Whales is small compared to the body.
The skull is characterised by the strong maxillary crests, enormously
developed in the male _Hyperoodon_. The vertex of the skull too is raised,
forming a pronounced prominence behind the aperture of the nares
(blow-hole); in many forms the rostrum is made of very dense bone, and is
thus relatively abundant in rock strata. The pterygoids meet in the middle
line as in the Cachalot. In addition to the few functional teeth in the
lower jaw there are more numerous but small teeth in the upper jaw. These
are not always to be recognised, as they are not attached to the bone, but
merely imbedded in the gums, so that they come away when the skull is
prepared.
The genus _Berardius_[250] differs from _Mesoplodon_ by its rather more
symmetrical skull, of which the vertex is formed by the nasals. The
mesethmoid is only partly ossified. The teeth are two on each side of the
mandible, with their apices directed forwards. The vertebral formula is
C 7, D 10, L 12, Ca 19.
_B. arnouxi_, from the seas of New Zealand, is the only species of this
genus which is well known. It is 30 or 32 feet in length, and is of a
velvety black colour, with a greyish belly. Instead of lowing like a cow,
this Whale has been described as "bellowing like a bull"! A singular and
somewhat inexplicable fact has been stated of this species. The teeth were
said to be protrusible, and Sir James Hector stated that the teeth were
imbedded "in a tough cartilaginous sac which adheres loosely in the socket
of the jaw, and is moved by a series of muscular bundles that elevate or
depress it." Sir William Flower justly observed that these statements
"accord so little with anything hitherto known in mammalian anatomy that
further observations on the subject are extremely desirable." Like other
Ziphioids, _Berardius_ feeds mainly, if not entirely, upon cuttle-fish, a
prey eminently suited to their almost toothless mouths. It is not known
whether _Berardius_ has the {369} Ziphioid grooves upon the throat. Nothing
is known of the structure of the internal viscera of this Whale. It appears
not to be really limited to the region of New Zealand, as is often stated,
for Malm has lately described a skull (_Berardius vegae_) from Bering's
Straits.[251]
_Mesoplodon_[252] is a world-wide genus embracing a number of species; on
the lowest estimate seven species can be distinguished, and Sir W. Flower
would add two more. These are moderate-sized Whales, 15 to 17 feet in
length. In the skull the mesethmoid is ossified; the nasals are sunk
between the upper ends of the premaxillae. There are but a single pair of
teeth in the mandible attached to nearly the middle of its length (whence
the generic name). The vertebral formula is C 7, D 9 or 10, L 10 or 11,
Ca 19 or 20. The sternum consists of four or five pieces. The amount to
which the cervical vertebrae are fused varies; but some are always fused.
The only species which has ever been stranded on the shores of this country
is _M. bidens_, an example of which was described many years ago as the
"Toothless Whale of Havre"; it was an old animal which had probably lost
its teeth. Nevertheless it received the separate generic and specific name
of _Aodon dalei_. The animal lived for two days out of the water, and made
a sound like the "lowing of a cow." An instance of the rarity of the Whales
of this genus is afforded by _M. europaeus_, of which only a single skull
is known; this was extracted from a dead body, found floating, about the
year 1840. It has never appeared since. _M. layardi_ is remarkable on
account of the very large size of its strap-shaped teeth; these curve over
the upper jaw in such a way as to prevent the animal from fully opening its
jaws. The case is curiously paralleled by the Sabre-toothed Tiger. This
species is antarctic in range. From the opposite extremity of the globe
comes _M. stejnegeri_, again known by but a single skull. It is singular on
account of the large size of the brain case, and is a native of Bering's
Straits. _M. hectori_ has its two teeth situated quite at the extremity of
the mandible, and in this feature approximates to the genus _Berardius_. It
was, indeed, confounded with that genus by one naturalist. {370}
_Ziphius_ is a genus which is also of world-wide range. Here again the
number of species is at present merely a matter of opinion. The prevalent
impression, however, is that but a single species exists, which will
therefore have the name of _Z. cavirostris_. The genus (and for the matter
of that the species too) may be thus characterised in comparison with its
allies. The mesethmoid is ossified as in _Mesoplodon_, but the nasals
joined together form the vertex of the skull. There are two teeth near the
symphysis of the mandible, besides the usual small and "functionless" teeth
in the upper jaw. The vertebral formula is C 7, D 9 or 10, L 11, Ca 21.
The throat of a _Ziphius_ from New Zealand was described by Messrs. Scott
and Parker[253] as having three grooves on each side. Whether this form is
the same as von Haast's _Z. novae zelandiae_ is a matter of doubt; but the
individual to which his name has been applied was 26 feet long, and had but
a single groove on each side. Even in the external characters of many
Whales many points require clearing up. Our knowledge of _Ziphius_ dates
from the year 1804, when a skull "completely petrified in appearance" was
picked up upon the Mediterranean coast of France, and described by the
great Cuvier. It was forty years before another specimen was found. In the
New Zealand specimen of von Haast already referred to, the body was scored
by numerous lacerations. These wounds may have been due to fights among the
Whales themselves; the forwardly-situated teeth would be capable of
inflicting such wounds. But it has also been stated that the armed suckers
of gigantic cuttle-fish are responsible for these scratches.
_Hyperoodon_ is the most easily-distinguishable genus of Ziphioid Whales.
Its characters are the following:--The skull has enormously-developed
maxillary crests in the adult male; the mesethmoid is not fully ossified.
There is but a single tooth to each ramus of the lower jaw, besides, of
course, the usual small teeth in the upper jaw. The vertebral formula is
C 7, D 9, L 9, Ca 18. The cervicals are fused into one mass, more or fewer
being free in other Ziphioids. The sternum consists of three pieces only,
the last of which is bifid posteriorly.
The name _Hyperoodon_ was given to this Whale by Colonel Lacepede on
account of the rough papillae upon the palate, which {371} were mistaken by
that observer for teeth. It is curious that the name is really appropriate
in spite of this mistake, though of course it would be so to all the
Ziphioids. In more than one feature this genus comes nearest of all the
Ziphiinae to _Physeter_. Its enormous maxillary crests are paralleled in
that Whale; but in _Hyperoodon_ their great thickness contrasts with the
thinness of those of the Cachalot. The correspondence in the attachment of
a rib to its vertebra by both heads is noteworthy. It is remarkable that in
this particular _Hyperoodon_ is more like _Physeter_ than the supposed
nearest ally of the latter--_Kogia_.
Of this genus two species are known. The best known is the common northern
_H. rostratum_ (with many aliases); the second species from the southern
hemisphere, _H. planifrons_, is only known from a single water- and
pebble-worn skull. Its identification, however, depends upon the known
accuracy of the late Sir William Flower.
The northern species (_Hyperoodon rostratum_) has often been recorded upon
our own coasts; the first record of the stranding of this Whale was in the
year 1717. In that year an example was found at Maldon, in Essex. Like the
Beluga, _Hyperoodon rostratum_ gets lighter in colour with advancing years.
The young are black; the old animals pale brown with some white about them.
The under surface, however, is always greyish white. The length of this
Whale reaches to at any rate 30 feet. But John Hunter had a specimen which
he believed to be 40 feet in length. The specimen, however, consisted only
of a skull, so that error might have crept in. It has already been
mentioned that the old males have enormous maxillary crests. According to
M. Bouvier, who has lately made an exhaustive examination of the anatomy of
this Whale,[254] the females occasionally exhibit the same crests, which
are thus presumably of the nature of spurs sometimes seen in old females
among the Gallinaceous birds. The number of grooves upon the throat is in
dispute in this Whale as in _Ziphius_. One pair is the usual allowance; but
Kuekenthal found four in some embryos studied by him. Attention has already
been called to the voice of Ziphioid Whales. _Hyperoodon_ neither "lows"
nor "bellows," but "sobs"! _Hyperoodon rostratum_ is a gregarious Whale,
going about in herds, or "gams" as they should technically be termed, of
four to ten or even fifteen. This Whale {372} can leap right out of the
water, and while in the air can turn its head from side to side, a
capability which has not been mentioned in any other Whale. It can also
stay under water for an unusually long period. Captain Gray,[255] who has
made an accurate study of this species, states that so long a period as two
hours is the limit of endurance; this event occurred in the case of a
harpooned Whale.
FAM. 2. DELPHINIDAE.--This family, which includes the greater number of
Cetacea, may thus be characterised:--Whales of small to moderate size.
Teeth as a rule numerous, and present in the upper as well as in the lower
jaw. Maxillae without large crests; the pterygoids, often meeting in the
middle line, enclose an air space open behind. The anterior (five to eight)
ribs are two headed, the posterior with tubercular head only. The sternal
ribs are ossified.
The Dolphins and Porpoises, as already stated, embrace the greater number
of existing species of Whales. Sir W. Flower and others who have followed
him, allow nineteen genera. But as to the exact number of known species
there is much uncertainty. That very careful observer, Mr. True,
considers[256] that there are fifty which demand recognition. As many as
one hundred have received names. The matter is one which is perhaps barely
ripe for decision. All the Dolphin tribe are, for Whales, smallish animals.
The Killer Whale, _Orca_, is the only genus (or species?) which usually
attains to more than moderate bulk. The rather mysterious _Delphinus
coronatus_, 36 feet in length, of M. de Freminville, would seem to be a
Ziphioid; it was described as having a very pointed beak, and as having the
dorsal fin situated near the tail; such characters suggest a _Mesoplodon_.
The genus _Delphinapterus_, the Beluga or White Whale, consists of but a
single species, though as usual more than one name has been given to
supposed different species. It is characterised as a genus by the following
assemblage of structural features:--It has only eight to ten teeth
occupying the anterior part of the jaws only. All the cervical vertebrae
are free and unjoined. The vertebral formula is C 7, D 11 (or 12), L 9,
Ca 23. The pterygoids are wide apart, though they converge as if about to
meet at their posterior ends. There is no dorsal fin. The colour is white.
{373}
The Beluga is a northern species purely. The reputed form, _D. kingii_, was
said to come from Australian seas; but there seems to have been an error in
this statement. It is interesting to note that the white colour, so
characteristic of the genus and species, is not found in the young, which
are blackish. They gradually pale as they advance towards maturity.
_Delphinapterus leucas_ reaches a length of 10 feet, and like other
Porpoises will ascend rivers in search of food. It is said to be specially
addicted to salmon. Among the contents of the stomach have been found
quantities of sand. But this habit of swallowing sand or pebbles has been
noted in other Whales. Whether it is or is not accidental (taken in with
ground-living food), it seems hardly likely that it is used for purposes of
ballast! The Beluga has a voice; but the name "Sea Canary" is hardly
suitable to it. A specimen of this species, recently described from the
shores of Scotland (it is often thrown up upon our coasts), which had got
entangled in the stakes of a new net, was regarded by the natives, on
account of its white colour, as a ghost. Externally, besides its colour,
the Beluga is remarkable for possessing a distinct neck, which is
correlated of course with the freedom of the cervical vertebrae, and is
also seen in Platanistidae.
The Narwhal (_Monodon_) is closely allied in structure to the last genus.
It has the following anatomical characters:--The teeth are reduced to a
single "horn" in the upper jaw, which is rudimentary in the female. The
neck vertebrae are free. The vertebral formula is C 7, D 11, L 6, Ca 26.
The pterygoids are as in _Delphinapterus_, and, as in that genus, there are
no hairs upon the face or dorsal fin.
This genus is of course most obviously characterised by the twisted tusk of
the male, which is occasionally double. This tusk has given to the only
species of the genus, _M. monoceros_, both its generic and specific name.
The animal has a spotted colour; but, as in the case of the Beluga, old
animals tend to become white. The use of its horn to _Monodon_ has been
debated. In the first place it is clearly a secondary sexual character. The
males have been observed to cross their horns like rapiers in a fencing
match. It may be that they are used in more serious combats. An ingenious
suggestion is that the long and strong tusk enables its possessor to break
the thick ice and {374} make a breathing hole. A third suggestion is due to
Scoresby, who was led to make it from having taken out of the stomach of a
Narwhal a large skate. He held that with its tusk the Whale empaled the
fish and then swallowed it. The Narwhal is not large, 15 feet or so in
length. But Lacepede, who was apt to compile with lack of discrimination,
speaks of 60 feet long Narwhals. _Monodon_ is purely Arctic, and but three
or four specimens have ever been cast up on our shores.
Of true Porpoises, genus _Phocaena_, there are apparently several species.
The genus itself has the following characters:--The teeth are sixteen to
twenty-six on each half of each jaw; their crowns are compressed and lobed.
The pterygoids do not meet. The dorsal fin has a row of tubercles along its
margin.
The Porpoise of our coasts, _P. communis_, is a smallish species 6 to 8
feet in length. There are two to four hairs present in the young; its
colour is black, generally lighter on the belly. The first six cervical
vertebrae are fused. The ribs vary in number from twelve to fourteen pairs.
It is a gregarious Whale, and will ascend rivers; it has been seen for
example in the Seine at Paris. The name Porpoise is often written
Porkpisce, which of course shows its origin. Very conveniently it was
regarded as a fish, and therefore allowed to be eaten in Lent. The
celebrated Dr. Caius, a gourmet as well as a physician and the refounder of
a college, invented a particular sauce wherewith to dress this royal dish.
Some time since Dr. Gray described a Porpoise from Margate as a distinct
species (see p. 342) on account of the tubercles, which are now known to be
a generic character.
Dr. Burmeister's _P. spinipennis_ seems, however, to be really distinct. It
was captured near the mouth of the Rio de la Plata. It is more tuberculated
on the fin and back, and has fewer teeth (sixteen as against twenty-six).
Mr. True's _P. dallii_ of the Pacific (where the Common Porpoise also
occurs) is characterised chiefly by its very long vertebral column,
consisting of ninety-eight vertebrae; there are only sixty-eight in the
other species. The Eastern genus _Neomeris_ is placed with _Phocaena_ by
Dr. Blanford. It practically only differs by the absence of a dorsal fin.
It is only about 4 feet long, and inhabits the seas of India, Cape of Good
Hope, and Japan. The one species is called _N. phocaenoides_.
The genus _Globicephalus_ is to be defined thus:--Teeth {375} seven to
twelve on each side, confined to anterior end of jaws. Skull raised into a
prominence behind the blow-hole; pterygoids large and in contact. Pectoral
fin long and falcate; dorsal fin present. No beak. Vertebral formula C 7,
D 11, L 11 to 14, Ca 27 to 29. Six pairs of the ribs are two-headed.
The best known species of the genus is the Ca'ing Whale, _G. melas_.[257]
This animal reaches a length of 20 feet, and is thus one of the largest of
the Delphinidae. It is gregarious and was, even is now, much hunted in the
Faeroe Islands. Its sheep-like habits (embodied in one scientific name
_deductor_) enable it to be easily driven on shore in herds, which are then
harpooned. The foetus of this Whale has a few hairs; the number of
phalanges in the two middle digits is very great, as many as eleven to
fourteen. _G. scammoni_, _G. brachypterus_, and _G. indicus_ are other
reputed species of the genus allowed by True and Blanford.
_Grampus_ is a genus allied to the last. It has no teeth in the upper jaw,
and but three to seven in the lower jaw, near the symphysis of the
mandible. The pterygoids are in contact. There is no beak, and the pectoral
fin is long. There are twelve pairs of ribs, of which six are two-headed.
Apparently there is but one species, _G. griseus_, known as "Risso's
Dolphin." It is a Mediterranean and Atlantic form, and is not common.
The genus _Orca_ has as characters:--Teeth ten to thirteen, long and
strong. Pterygoids not quite meeting. Vertebrae C 7, D 11 to 12, L 10,
Ca 23. The first two or three fused. The dorsal fin is long and pointed.
Of this genus there may be more than one species; but the best known is the
Killer Whale, _O. gladiator_ (Fig. 180, p. 341), often spoken of as the
"Grampus."[258] It is marked with contrasting bands of white or yellow upon
a black body-colour. The animal grows to a considerable length, as much as
30 feet. _Orca_ is a powerful and rapacious Whale; and Eschricht has stated
that from the stomach of one, thirteen Porpoises and fourteen Seals were
extracted. They will also combine to attack larger Whales, and Scammon has
related how he witnessed such an onslaught upon a Californian {376} Grey
Whale. "Belua truculenta dentibus," observed Olaus Magnus of this Cetacean.
The high dorsal fin has been much exaggerated in old drawings; it has been
even represented as strong and sharpened at the end, so as to be capable of
ripping open the belly of a Whale. The fact that it sometimes lies over a
little to one side is responsible for another anecdote: that an example of
this Whale was seen to retire with a couple of Seals tucked away under the
flippers, another grasped by the dorsal fin, and a fourth in the mouth!
"When an Orca pursues a whale," wrote Dr. Frangius, "the latter makes a
terrible bellowing like a bull when bitten by a dog." It is probable,
according to F. Cuvier, that this Whale is the "Aries marinus" of the
ancients, certain bands of white upon the head giving an impression of
curved horns. It may also be the "horrible Sea-satyre" of Edmund Spencer.
Allied to _Orca_, but distinguishable from it by some rather minute
peculiarities, is _Pseudorca_. It may be thus defined:--Teeth eight to ten,
much like those of _Orca_. Dorsal fin rather small, falcate. Vertebral
formula C 7, D 10, L 9, Ca 24. Six or all the cervicals united. The curious
fact about this Whale, which embraces only a single species, _P.
crassidens_, is that it was first known in the fossil condition from
remains discovered in the fens of Lincolnshire. An important day for
cetologists was that on which a whole herd entered the Baltic and furnished
material for a better study of this Whale. It is not, any more than its
near ally _Orca_, confined to northern seas; for several examples, at first
relegated to a distinct species (_P. meridionalis_), have been obtained
from the seas round Tasmania.
_Orcella_ (which has been written _Orcaella_) has fourteen to nineteen
small sharp teeth in each half of each jaw. The pterygoids are widely
separate. The dorsal fin is small and falcate. The vertebral formula is
C 7, D 14, L 14, Ca 26. Seven ribs are two-headed, and five of them reach
the sternum.
This genus contains but a single species, _O. brevirostris_, which is both
marine and fresh-water in habit; it occurs in the Indian seas, and in the
Irrawaddy even as far up as 900 miles from the sea. Some regard the
fresh-water individuals as a distinct form, _O. fluminalis_.
_Sagmatias_ is a genus known only from a skull, which is remarkable for the
elevation of the premaxillae into a crest; the {377} pterygoids are short,
and there are thirty-two teeth in each half of each jaw.
_Feresia_ is known from two skulls which are provided with ten to twelve
teeth in each half of each jaw. It is intermediate between _Globicephalus_,
_Grampus_, and _Lagenorhynchus_, according to Sir W. Flower.
The genus _Delphinus_ contains the Dolphin, _D. delphis_.[259] The genus
may be characterised as follows:--Teeth small and numerous, forty-seven to
sixty-five. Vertebral formula C 7, D 14 or 15, L 21 or 22, Ca 30 to 32. The
atlas and axis are fused, the rest free. The palatal border of the maxillae
is deeply grooved. The fins are falcate; the beak long and distinct.
The Common Dolphin of the Mediterranean shows so many variations of colour,
slight differences in the proportions of the bones of the skull, and in the
number of the teeth, that it has been divided up into at least seventeen
"species." But M. Fischer, who has studied many of these forms, does not
admit them, and most students of this group of mammals follow him in the
matter. The Dolphin is and has been the most familiar of Cetaceans; in
consequence it has accumulated much anecdote of a mythical character. The
extreme intelligence and goodwill towards man assigned to this creature by
the ancients are possibly due to the anomaly of a creature ostensibly a
fish showing many of the characters of higher animals. Its unfishlike
intelligence baffled the early observers, who at once endowed it with
especially advanced attributes. Hence the stories of Arion and others. The
leaping of the Dolphin out of the water is exemplified in many
Mediterranean coins and coats of arms; the heraldic dolphin is represented
with an arched back as in leaping. The Dolphin reaches a length of some 7
feet, and appears to be world-wide in range. Possibly distinct is _D.
longirostris_, characterised, as the name denotes, by the very long beak;
it has also more teeth and is a native of Malabar. _D. roseiventris_ again
may be a third species of _Delphinus_. It comes from Torres Straits, and
has the under parts rosy in colour.
The genus _Prodelphinus_ has, like _Delphinus_, a distinct beak; but it has
not the grooved maxillaries. No other character of importance appears to
separate it from _Delphinus_. {378}
The genus consists of some eight widely distributed species, which are none
of them large Dolphins.
_Lagenorhynchus_ has the following assemblage of characters:--Head with
short, not very distinct beak. Dorsal and pectoral fins falcate. Teeth
small, twenty-two to forty-five in each half jaw. Vertebrae ranging in
number from seventy-three to ninety-two. Pterygoid bones either in contact
or separate. There are fifteen or sixteen pairs of ribs, of which six are
two-headed. Of this genus Mr. True allows eight species, which have been
increased by a ninth since the publication of his "Revision."[260]
Two species of _Lagenorhynchus_ are known from our coasts; the rest are
mainly southern in range. The British species are, firstly, _L.
albirostris_, a Dolphin of some 9 feet in length. It has a large number of
vertebrae, ninety-two in number. _L. albirostris_ is a rare species, the
first record of its occurrence on these shores being in 1834. Since that
date some eighteen individuals have been shot or stranded on the shores of
the British Isles. The second British species, _L. acutus_, differs in
colour from the first. As in the last, the upper parts are black and the
under parts white; but in _L. acutus_ there is also a stripe on the flanks,
brownish in colour. It has fewer vertebrae, not more than eighty-two.
The next genus of Dolphins, _Sotalia_, is characterised by--Teeth tolerably
large, twenty-six to thirty-five. The vertebral formula is C 7, D 11 or 12,
L 10 to 14, Ca 22. The pterygoids are not in contact in the middle line. It
has a distinct beak.
Of this genus there are some six species (the exact number, as in so many
other genera, cannot be positively asserted), most of which are fluviatile
or estuarine in habit. They are also on the whole characterised by their
pale, if not actually white, coloration. _S. sinensis_ of the Amoy is white
with pinkish fins. _Sotalia guianensis_ is American as its name denotes. It
is figured by van Beneden as of a pale brown colour. It is very abundant in
the Bay of Rio de Janeiro, and has the reputation of being a friend of man
like some other Dolphins. The natives hold that it will bring to shore the
bodies of drowned persons. The most singular species of the genus is that
recently described by Professor Kuekenthal as _S. teueszii_.[261] This
animal is purely fresh-water, being found in {379} the Camaroon river,
where it is extremely rare. The nostrils (blow-hole) are prolonged into a
snout-like process, a fact which is of interest in connexion with the
assertion that in _Balaenoptera_ the blow-hole is puffed out during
spouting. What is temporary in the Rorqual appears to be permanent in the
_Sotalia_. More remarkable still, perhaps, is the assertion that it is a
vegetable-feeding Dolphin. This is not a mere assertion except that it may
not apply universally; for in the stomach of a specimen nothing but
vegetable debris was found. But in the stomachs of other Whales (e.g.
_Rhachianectes_) vegetable matter has also been found, which may perhaps
have been taken in accidentally with the food.
_Steno_ comes near _Sotalia_, and Dr. Blanford has transferred to it (under
the one name of _Steno perniger_) the two species, _Sotalia gadamu_ and
_Sotalia lentiginosa_. It is, however, to be distinguished from _Sotalia_
by the following characters:--Teeth large and few, twenty to twenty-seven
on each side of each jaw, with furrowed surfaces to crowns. Vertebrae C 7,
D 12 or 13, L 15, Ca 30 to 32. Pterygoids in contact. There are but two
species apparently (not counting Dr. Blanford's).
_Tursiops_ is not a very easily definable genus. These are its chief
features:--Teeth large, twenty-two to twenty-six in number in each half of
each jaw. Vertebral formula C 7, D 12 or 13, L 16 or 17, Ca 27. Pterygoids
in contact. Beak distinct. Some five species are allowed; but it seems to
be difficult to differentiate the others from _Tursiops tursio_. This, the
best-known form, is quite or nearly world-wide in range, and occurs, though
not abundantly, on our own coasts. Mr. True has observed that the eyelids
of this Whale, which is largely hunted on the American coast, are as mobile
as those of a terrestrial mammal. The name "tursio" is derived from Pliny.
Belon would also derive from this word the French vernacular "marsouin."
The latter term is sometimes regarded as a corruption of "Meerschwein," but
it would seem to be more probably derivable from "marinum suem," from the
Latin direct. _T. tursio_ has the back black to lead-colour; the under
parts white. In the reputed species, _T. abusalam_, from the Red Sea, the
back is a dark sea-green. _T. tursio_ reaches a length of 12 feet, but is
more usually smaller.
The genus _Tursio_ must be carefully distinguished from {380} _Tursiops_.
It has no dorsal fin, the teeth are small and numerous (forty-four), and
the pterygoids are separate. There are two species, _T. borealis_ and _T.
peronii_, the former being northern and the latter more widely spread.
The genus _Cephalorhynchus_ has for its chief characters the
following:--Teeth twenty-five to thirty-one, small and sharp. Pterygoids
widely separated. Dorsal fin not falcate, but triangular or ovate in form.
Beak not well marked off from the head. The species of this genus are all
southern in range; four are perhaps to be allowed.
FAM. 3. PLATANISTIDAE.--This family of Odontocetes may be distinguished
from the Dolphins by the following assemblage of structural
features:--Cervical vertebrae all free, and each one of some length (for a
Cetacean). Jaws long and narrow, with a considerable length of symphysis.
Teeth very numerous.
This very meagre series of differential characters is largely due to
_Pontoporia_ on the Platanistid side, and to _Monodon_ and _Delphinapterus_
upon the Delphinid side. Otherwise the family Platanistidae would be
extremely distinct. The two last-named genera have separate cervical
vertebrae, and in the Beluga at any rate this is expressed externally by a
quite distinct neck. Moreover, as Mr. True has pointed out, the pterygoid
bones have not the involuted cavity below which characterises other
Dolphins; and they have, what other Dolphins have not, an articulation
outwards with the roofing bones of the skull. Sir W. Flower described the
fact that in Inia (and the same occurs in Pontoporia) the palatines are
separated from each other by the intervention of the vomer. In this feature
they resemble certain Ziphioids, _Berardius_, _Oulodon_ (= _Mesoplodon_)
_grayi_, and _Hyperoodon_. The true Dolphins also appear to show the same
intervention of the vomer in a few cases. There is nothing, therefore,
distinctive from the Delphinidae in this feature.
The existence of cartilaginous sternal ribs in _Inia_ and _Platanista_
shows affinity between these two genera and the Physeteridae. _Pontoporia_
is Dolphin-like in this particular, as it is also in the mode of
articulation of the ribs with the vertebral column. But this last matter
has already been dealt with. The principal reason for placing _Pontoporia_
with the other two genera is the close resemblance which its skull bears to
that of _Inia_.
The first genus of this family which will be noticed is _Platanista_. {381}
The following are its main characters:--Dorsal fin absent. Eyes
rudimentary. Pectoral fins large and truncated at the extremity. Teeth,
about twenty-nine in each half of each jaw. Scapula with the acromion
coinciding with its anterior edge. Skull with enormous maxillary crests,
and with the palatines entirely concealed by the pterygoids. The length of
the above definition will serve to indicate how anomalous in many
particulars is the structure of this "Dolphin."
There is apparently but one species, _P. gangetica_, the "Susu." The Indian
vernacular name is derived from the sound that the animal makes when
spouting. It is an inhabitant of the Ganges and the Indus, together with
their tributaries, and ascends very high up its streams. It is also thought
to be purely fluviatile and never to desert the rivers for the sea.
_Platanista_ lives chiefly by grubbing in the mud for prawns and fish.
Grains of rice have also been found in the stomach, but this would seem to
be accidental. The long snout of the Susu has been compared to the long
snout of the Gharial, a native of the same region. This Whale grows to a
length of over 9 feet, but this length is exceptional. Its anatomy has been
elaborately described by Dr. Anderson.[262]
The next genus, _Inia_, is thus to be characterised:--Dorsal fin
rudimentary; pectorals large and ovate. Teeth, as many as thirty-two on
each side, often with an additional tubercle. Skull without large maxillary
crests; palatines not hidden by pterygoids, but divided by vomer. The
vertebrae of this genus are few in number, only forty-one in all, which are
thus distributed: C 7, D 13, L 3, Ca 18. The peculiarities of the vertebral
column are several. In the first place, as has been mentioned in the
definition of the family, all the cervicals are separate and individually
of some length. Secondly, the axis has a better trace of an odontoid
process than in any other Whale except _Platanista_, where it is even more
obvious. The lumbar region is remarkable on account of its restriction to
three vertebrae. The sternum, by what we must regard as convergence, is
somewhat like that of the Whalebone whales. It consists of one piece only,
of a roughly-oval form, to which apparently only two pairs of
(cartilaginous) sternal ribs are attached. In the fore-limb the proportions
between the humerus and the radius are more like {382} those of terrestrial
mammals; _i.e._ the humerus is distinctly the longer, the converse usually
obtaining among Whales. But _Platanista_ again agrees with _Inia_. The
teeth are remarkable for the fact that the hindermost ones of the series
have an additional lobe; they are not purely conical as are those of Whales
generally.
There is but one species, _Inia geoffrensis_, which inhabits the Amazons,
and grows to a length of 8 feet. Its colour variations are rather
extraordinary, unless they can be set down to sex, which has been denied.
Some individuals are wholly pink; others are black above and pink beneath.
This Whale is believed by the Indians to attack a man in the water, and it
is added that the _Sotalia_ of the same streams will defend him from these
attacks! Naturally, therefore, superstitious reverence attaches to this
Dolphin, which is tiresome to the naturalist who wants specimens, as
Professor Louis Agassiz found.
In the genus _Pontoporia_[263] the dorsal fin is well developed and
falcate. The teeth are very numerous, 200 in all. The ribs articulate as in
Dolphins. The skull closely resembles that of Inia, and the scapula is, as
in that genus, "normal."
The proper name for _Pontoporia_ is really _Stenodelphis_, which name was
first used by Gervais a month or two before Gray, who separated it from the
vague _Delphinus_ of its original discoverer, Gervais himself. It has a
longer snout than _Inia_, which, being bent towards the extremity in a
downward direction, curiously suggests the skull of a Curlew. In details,
however, the skull is exceedingly like that of _Inia_. It is nearly
symmetrical. The vertebral formula appears to be the following:--C 7, D 10,
L 5, Ca 20 = 42, just one over the number of the vertebrae in _Inia_. The
sternum is in two pieces. Of the ten pairs of ribs the first three are
double-headed. These and the next have sternal moieties joining the
sternum, of which the first three are ossified, the last being apparently
merely a ligament.
There is a single species of the genus, _P. blainvillii_. This Whale is
described by Mr. Lydekker as being of a clear brown colour, harmonising
with the waters of the estuary of the Amazons and the La Plata which it
inhabits. The same colour characterises _Sotalia pallida_ of those parts of
the world, and {383} may be a colour adaptation. But the extant accounts of
the colour of this Dolphin vary--quite possibly in accordance with real
variations, such as are exhibited by _Inia_ already spoken of. _Pontoporia
blainvillii_ is a smallish Dolphin some 4 feet in length.
FOSSIL ODONTOCETES.--Several of the existing genera of Dolphins are also
known in a fossil condition, as well as Ziphioid Whales closely related to
existing forms. We shall deal here only with a few genera of fossil
Odontocetes which depart in their structure from existing forms.
The genus _Physodon_ is Miocene, and has been found in Patagonia. It
appears to be most nearly allied to the Physeteridae, but should probably
form a distinct family. _Physodon_ was not so large as _Physeter_, the
skull measuring only some 10 feet. It thus comes nearer in point of size to
_Kogia_, and it is interesting to note that its relatively-shorter snout is
also suggestive of the dwarf Cachalot. The general outline of the skull is,
however, more like that of _Physeter_, and there is the same deep cavity
for the lodgment of spermaceti. The main feature of interest in the skull
is the presence of teeth in both jaws, and the fact that two or three are
lodged in the premaxillae. This is precisely what is found in the most
ancient Whales, the Zeuglodonts.
Extinct Dolphins, apparently referable to the Platanistidae, are the most
numerous among the earlier forms of Cetaceans, and it is significant that
the earliest known forms of these go back to the Eocene.