_Apolectus_, _Nematistius_, _Seriola_, _Seriolichthys_, _Naucrates_,
_Trachynotus_, _Zalocys_, _Lichia_, _Paropsis_, _Chorinemus_. Species of
_Caranx_, _Mene_, and _Seriola_ have been described from the Eocene and
Miocene of Europe, in which occur also the fossil genera named
_Vomeropsis_, _Archaeus_, _Carangopsis_, _Carangodes_, _Ductor_, and
_Semiophorus_.
The family is represented on our coasts by the common Horse-Mackerel,
_Caranx trachurus_. The young of this species keep together in small bands
in the neighbourhood of medusae, under which they seek shelter when
disturbed. The Pilot-Fish, _Naucrates ductor_, is a truly pelagic fish of
wide distribution, which occasionally appears on our coasts, accompanying
large sharks and ships. Much has been written on the marvellous habits of
this little fish, which is said to lead the shark like a pilot, directing
it to its food, in exchange for which services the pilot enjoys protection
from the fear which the proximity of its formidable companion inspires to
its enemies among other carnivorous fishes, and an abundance of food from
the shark's excrements.[722]
FAM. 2. RHACHICENTRIDAE.—Praemaxillaries slightly protractile. Vertebrae 25
(11 + 14), without well-developed parapophyses; ribs and epipleurals
inserted close together on the centra. Body covered with very small scales;
a series of short isolated dorsal spines; soft dorsal and anal long;
pectorals {678}inserted low down. A single genus, _Rhachicentrum_
(_Elacate_), with a single species from the coasts of the tropical and
warmer parts of the Atlantic and of the Indian Ocean.
FAM. 3. SCOMBRIDAE.—Praemaxillaries large, not protractile, beak-like.
Vertebrae 30 to 50, without transverse processes, but some of the hinder
praecaudals with haemal arches; ribs inserted on the centra or on the
haemal arches when these are present; epipleurals all on the centra. Scales
cycloid and usually very small (except in _Gastrochisma_), sometimes
absent. A spinous dorsal fin formed of slender spines, folding into a
sheath; soft dorsal longer and broken up into finlets, similar to the anal;
pectoral inserted high up the sides. Hypural bones completely embraced by
the forked bases of the caudal rays. Pseudobranchiae present.
[Illustration: FIG. 415.—Tunny (_Thunnus thynnus_). (After Cuvier and
Valenciennes.) × ⅛.]
About 50 species, referred to the following genera:—_Scomber_, _Auxis_,
_Thunnus_, _Sarda_, _Cybium_, _Acanthocybium_, _Gastrochisma_
(_Lepidothynnus_). Numerous fossil representatives in Tertiary beds,
belonging to _Scomber_, _Auxis_, _Thunnus_, _Cybium_, and to the extinct
genera _Eothynnus_, _Isurichthys_, _Palimphyes_, _Scombrinus_,
_Sphyraenodus_, _Scombramphodon_.
These fishes, elegant in form and often in colour, are among the swiftest
of the inhabitants of the sea. Some are migratory, like the Mackerel
(_Scomber scombrus_) of the North Atlantic, whilst others are remarkable
for their wide distribution. The Tunny (_Thunnus thynnus_), for instance,
the largest member of the family, reaching a length of 10 feet, inhabits
the Atlantic, Pacific, and Indian Oceans, extending as far north as the
British {679}seas, Newfoundland, California, and Japan. It supplies
important fisheries in France and Italy. The Tunnies are the only fish
known to be warm-blooded.
FAM. 4. TRICHIURIDAE.—Praemaxillaries not protractile. Vertebrae 32 to 160,
without transverse processes; ribs sessile, on the centra or on the haemal
arches when these are present; epipleurals, if well developed, on the
centra. Scales very small or absent. Spinous portion of dorsal fin much
longer than the soft, the spines more or less feeble. Pectoral fins
inserted low down the sides. Pseudobranchiae present.
The members of this family show a great variation in the shape of the body,
which, although always strongly compressed, is not unlike that of a
Mackerel in the more normal types, such as _Thyrsites_ and _Ruvettus_,
whilst, through a chain of genera, it generally assumes an extremely
elongate form; concurrently with this elongation of the body, the dorsal
fin loses its differentiation into two portions, the ventrals become
reduced and disappear, as in the Scabbard- or Frost-Fish (_Lepidopus
caudatus_), while the caudal fin decreases in size, loses its fork-shape,
and is finally lost in _Trichiurus_, in which the body is ribbon-shaped and
tapers to a point.
About 25 species are known, pelagic and widely distributed, many descending
to great depths.
Principal living genera: _Ruvettus_, _Thyrsites_, _Epinnula_, _Nesiarchus_,
_Nealotus_, _Promethichthys_, _Dicrotus_, _Gempylus_, _Aphanopus_,
_Lepidopus_, _Euoxymetopon_, _Benthodesmus_, _Eupleurogrammus_,
_Trichiurus_.
Remains of several species referred to _Thyrsites_, _Lepidopus_, and to the
extinct genera _Thyrsitocephalus_, _Hemithyrsites_, and _Trichiurichthys_,
have been found in the Oligocene and Miocene of Europe.
FAM. 5. HISTIOPHORIDAE.—Praemaxillaries not protractile; snout produced
into a spear-shaped rostrum; a praedentary bone; teeth minute. Body
elongate, covered with small or rudimentary scales. Vertebrae 24 or 25,
without transverse processes; ribs sessile; no epipleurals. One or two
dorsal fins, without a distinctly spinous portion. Pectoral fin low down
the side. Pseudobranchiae present.
The Sail-Fishes are large oceanic fishes, endowed with great strength and
swiftness, occurring in the tropical and sub-tropical {680}seas. Four or
five species are distinguishable, and are referable to two genera:
_Histiophorus_, with a single dorsal fin and 2 or 3 ventral rays, and
_Tetrapturus_, with the dorsal divided into two parts and a single ventral
ray.[723]
Fossil Histiophoridae are known from the Eocene and later beds in Europe
and America. Dr. A. S. Woodward observes that the known fossils are too
imperfect to be referred with certainty to their respective genera. Most of
them probably belong to _Histiophorus_, but at least one genus from the
Eocene (_Xiphiorhynchus_) appears to be well distinguished.
[Illustration: FIG. 416.—_Tetrapturus belone_, from the Mediterranean.
(After Cuvier and Valenciennes.) × ⅒.]
The imperfectly known extinct family PALAEORHYNCHIDAE, from the seas of the
Eocene, Oligocene, and Miocene periods, with the genera _Palaeorhynchus_
and _Hemirhynchus_, is probably closely related to the Histiophoridae. The
vertebrae number 50 to 60, and the ribs completely encircle the body. In
_Palaeorhynchus_ both jaws are equally produced into an ensiform weapon.
_Blochius_, from the Eocene, with diamond-shaped, slightly overlapping bony
scutes on the body, is perhaps also to be placed near this family.
{681}FAM. 6. XIPHIIDAE.—Differs from the preceding in the absence of
praedentary bone, and in the vertebrae (26 in number), which in the
praecaudal region are provided with short but well-developed transverse
processes, to which the short ribs are attached. Ventral fins absent, the
pectorals being inserted in the place usually occupied by them. Adult
without teeth or scales.
A single species, the Sword-Fish (_Xiphias gladius_), of nearly world-wide
distribution, occurring occasionally on the coasts of Great Britain and
Ireland.
FAM. 7. LUVARIDAE.—Mouth small, praemaxillaries not protractile, with very
feeble dentition. Gill-membranes attached to the isthmus. Vertebrae 23,
without transverse processes; ribs blade-like, inserted on the centra; no
epipleurals. Body rough, with minute scales. Dorsal and anal fins elongate,
formed of unarticulated, widely set rays. Pectoral fins inserted rather low
down; ventrals much reduced, the two halves of the pelvis fused into a
single bone. Supraclavicle fused with the forked post-temporal. Hypural
bones completely embraced by the forked bases of the caudal rays.
Pseudobranchiae present.
_Luvarus imperialis_, a rare pelagic fish from the Atlantic, Mediterranean,
and Pacific, growing to a length of 6 feet, and occasionally captured on
our coasts, is the only representative of this family. Very little is known
of the habits of this strange fish. The excessive length of the intestines
and the feeble dentition point to its feeding partly on vegetable matter,
partly on minute animals; the circumstances under which certain specimens
were captured tend to indicate that they follow up streams of pelagic life
such as engage the attention of the Basking Shark, of similar distribution.
FAM. 8. CORYPHAENIDAE.—Praemaxillaries small, not protractile. Vertebrae 30
to 33, without transverse processes; ribs and epipleurals attached close
together on the centra. Body elongate; scales small, cycloid or elongate
lanceolate. Dorsal and anal fins much elongate, without distinct spines.
Pectoral fins inserted rather low down the side. Pseudobranchiae absent.
The "Dolphins" (_Coryphaena_), of which only two species can be
distinguished, are large pelagic fishes, of carnivorous habits, pursuing
the Flying-Fish. They grow to a length of 6 feet, and their flesh is much
valued. Their deep head, with short snout, {682}and their long posteriorly
attenuate body ending in a large forked caudal fin, give them a peculiar
appearance.
FAM. 9. BRAMIDAE.—Praemaxillaries small, not or but feebly protractile;
maxillaries large, scaly. Vertebrae 42 to 47, the praecaudal without
transverse processes, but mostly with hæmal arches to which the ribs are
attached, the epipleurals being inserted on the centra. Body deep; scales
moderate or large, strongly imbricate, with processes which, in certain
parts at least, serve to connect the rows of scales. Dorsal and anal
elongate, some or all of the rays simple, but not forming true spines.
Pectoral inserted rather low down the side, freely movable upwards and
downwards. Pseudobranchiae present.
Pelagic fishes, often descending to great depths. About 12 species are
known,[724] referable to 6 genera: _Brama_, _Taractes_, _Pterycombus_,
_Pteraclis_, _Bentenia_, and _Steinegeria_. _Taractes_, often confounded
with _Brama_, differs from it not only in the larger, keeled scales, but
also in the protractile mouth and in the much greater development of most
of the ribs, which form curved lamellae of great width.[725] _Pteraclis_ is
very remarkable for the enormous, sail-like dorsal and anal fins.
DIVISION III.—ZEORHOMBI.
Aberrant, strongly compressed Perciformes, with very short praecaudal
region, modified much as in the Flat-Fishes, culminating in asymmetrical
forms, and characterised by the combination of an increased number (7 to 9)
of ventral rays, with absence of hypural spine (by which the Berycidae are
excluded), _or_ by asymmetry of the skull in the forms in which the spine
of the ventral fin has been lost.
Among the symmetrical forms, the existing Zeidae agree with the Berycidae
in having more than five soft rays to the ventral fins, and are probably
derived, together with the Eocene Amphistiidae, from some common ancestral
group still to be discovered in Cretaceous beds. These Zeidae have much in
common with the Pleuronectidae,[726] and might be regarded as {683}forming
part of the family out of which the latter have sprung, were it not that
they have lost the last half-gill. _Amphistium_ is probably more nearly
related to the Pleuronectidae, which may have been directly derived from
the family of which it is as yet the only known representative.[727]
This division embraces three families only:—
A distinct spinous dorsal fin; anal spines detached from the soft
portion; a ventral spine; gills three and a half, four slits between
them 1. _Zeidae_.
Dorsal and anal spines few, continuous with the soft rays; a ventral
spine 2. _Amphistiidae_.†
No spines; cranium twisted in front, with the two orbits on one side;
gills 4, a slit behind the fourth 3. _Pleuronectidae_.
† Extinct.
FAM. 1. ZEIDAE.—No subocular shelf; praemaxillaries strongly protractile.
Gill-membranes free from isthmus; 7 or 8 branchiostegal rays; gills 3½;
pseudobranchiae well developed. Lower pharyngeal bones separated. Vertebrae
30 to 46, the anterior with sessile ribs, the posterior praecaudals with
long neural spines bent forwards and with transverse processes directed
downwards, forming haemal arches and bearing the ribs at their extremity;
epipleurals much reduced or absent; hypural large, without the basal spine
or knob present in most Perciformes and all Scombriformes and Percesoces,
bearing fewer than 20 rays. Dorsal and anal fins elongate, the former with
a distinct spinous portion, the latter with 1 to 4 spines detached from the
soft portion. Pectoral fin supported by 4 pterygials, of which 3 are in
contact with the perforated scapular bone; post-temporal forked and solidly
attached to the skull. Ventral fin with 1 spine and 6 to 8 soft rays.
Scales small or minute, sometimes hard and rough and firmly joined in
vertical series; bony plates may be present along the base of the vertical
fins. Air-bladder present.
Twelve species are known from the Atlantic and Pacific Oceans, referable to
5 genera: _Grammicolepis_, _Cyttus_, _Cyttopsis_, _Zenion_, and _Zeus_.
_Oreosoma_ was founded on a young form of a fish allied to _Cyttus_.
Remains of _Zeus_ occur in the Oligocene, and _Cyttoides_, from the same
period, has been compared with _Cyttus_.
The well-known John Dory (_Zeus faber_) is much valued for the table.
{684}FAM. 2. AMPHISTIIDAE.—The only known representative of this family,
the Upper Eocene _Amphistium paradoxum_, originally described as a
_Pleuronectes_, has much in common with the Zeidae, from which it differs
in the smaller number of vertebrae (10 + 14), and in the dorsal and anal
spines being more reduced, adnate and continuous with the series of soft
rays; the scales are more normal and imbricate; ventral fins with 1 spine
and 8 soft rays. This fish appears to realise in every respect the
prototype of the Pleuronectidae before they had assumed the asymmetry which
characterises them as a group.
[Illustration: FIG. 417.—Restoration of _Amphistium paradoxum_. × ½.]
FAM. 3. PLEURONECTIDAE.—Head asymmetrical, the skull twisted in front, with
the two orbits on one side in the adult; the side of the body bearing the
eyes and turned upwards in life being coloured, the other side colourless
and blind. Mouth more or less protractile. Gills 4, a slit behind the
fourth; pseudobranchiae present. Lower pharyngeal bones usually separated,
rarely imperfectly united. Vertebrae 24 in the most generalised form
(_Psettodes_), varying from 28 to 65 in others, the praecaudals mostly with
more or less developed transverse processes, which may be directed
downwards and become converted into haemal arches; ribs and epipleurals
present. Caudal fin, if well developed, supported by a large hypural
usually without basal spine or knob. Dorsal and anal fins much elongate,
without spines, the former often extending on the head. Paired fins often
reduced, {685}sometimes absent; if fully developed and normally formed, the
bones of the pectoral and pelvic girdles as in the Zeidae. Ventral fins
usually with 5 to 7 soft rays.
Scales usually imbricate, cycloid or ctenoid; rarely absent; bony tubercles
sometimes present. Air-bladder absent.
Most species, and even genera, are either sinistral or dextral, but this is
inconstant in some, including the most generalised genus, _Psettodes_. The
very young are transparent and symmetrical, with an eye on each side, and
swim in a vertical position like other Fishes. These larval forms have been
described as distinct genera, under the names of _Peloria_, _Bibronia_,
_Charybdia_, etc. As they grow, the eye of one side moves by degrees to the
other side, where it becomes the upper eye. If at that age the dorsal fin
does not extend to the frontal region, the migrating eye simply moves over
the line of the profile, temporarily assuming the position which it
preserves in _Psettodes_, _Atheresthes_, and _Platysomatichthys_; in other
genera, the dorsal fin has already extended to the snout before the
migration takes place, and the eye, passing between the frontal bone and
the tissues supporting the fin, appears to pass from side to side through
the head, as was believed by some of the earlier observers.[728]
Flat-fishes are a large group of some 500 species, mostly marine, a few
species related to the Soles being confined to the fresh waters of South
America and the Malay Archipelago. They range from the Arctic Circle to the
southern coasts of the Southern Hemisphere; many occur at great depths
(_Citharichthys dinoceros_ down to 955 fathoms). Well-preserved remains
referred to _Psetta_ occur in the Upper Eocene, and a species of _Solea_ is
known from the Lower Miocene.
{686}[Illustration: FIG. 418.—Outlines of various Pleuronectids, showing
differences of form. A, _Psettodes erumei_; B, _Pleuronectes platessa_; C,
_Psetta maxima_; D, _Solea vulgaris_; E, _Cynoglossus lingua_.]
{687}A satisfactory classification of the Pleuronectidae is still a
desideratum, and cannot be attempted until the osteology of the very
numerous forms has been thoroughly studied. Even the division into two
principal groups, regarded by some recent authors as families,
Pleuronectidae and Soleidae, is based on characters which the examination
of a large number of generic types shows not to be constant. Thus the
former have been defined as having the praeopercular margin distinct
externally, the snout not projecting beyond the mouth, the nostrils of the
two sides on the coloured side or those of the blind side high up near the
dorsal line of the head; the latter as having the praeoperculum hidden
under the skin, the snout projecting more or less beyond the mouth, and the
nasal organ of the blind side similarly situated to that of the eyed side.
However, the genera _Aphoristia_ and _Peltorhamphus_, and others among the
Soles, show exceptions to this definition.[729]
Principal genera: _Psettodes_, _Atheresthes_, _Platysomatichthys_,
_Hippoglossus_, _Hippoglossoides_, _Hippoglossina_, _Poecilopsetta_,
_Chascanopsetta_, _Paralichthys_, _Pleuronectes_, _Glyptocephalus_,
_Citharus_, _Rhomboidichthys_, _Psetta_ (_Rhombus_), _Arnoglossus_,
_Zeugopterus_, _Lepidorhombus_, _Ammotretis_, _Rhombosolea_, _Solea_,
_Achirus_, _Achiropsis_, _Soleotalpa_, _Synaptura_, _Ammopleurops_,
_Aphoristia_, _Cynoglossus_, _Symphurus_ (_Plagusia_).
The following are the principal British representatives which are valued as
food:—The Halibut (_Hippoglossus vulgaris_), by far the largest of all
Flat-Fishes, growing to a length of 10 feet or more; the Long Rough Dab
(_Hippoglossoides limandoides_); the Plaice (_Pleuronectes platessa_); the
Flounder (_P. flesus_), which ascends streams; the Dab (_P. limanda_); the
Smear Dab, often called Lemon Sole (_Glyptocephalus microcephalus_); the
Witch (_G. cynoglossus_); the Megrim or Whiff (_Lepidorhombus megastoma_);
the Turbot (_Psetta maxima_); the Brill (_P. laevis_); and the Sole (_Solea
vulgaris_).
DIVISION IV.—KURTIFORMES.
No bony stay for the praeopercle. Dorsal spines feeble, few. Scapula
absent, the coracoid supporting four small pterygials. Ventral fins
thoracic.
FAM. 1. KURTIDAE.—The genus _Kurtus_, with a single species, from the
Indian and Pacific Oceans, forms an isolated, very {688}aberrant group. The
strongly compressed body is covered with minute, rudimentary scales; the
dorsal is short, with few, graduated spines, and the anal much elongate,
with 2 small spines; the ventrals are formed of 1 spine and 5 soft rays.
The vertebral column consists of 24 vertebrae; the ribs of the third and
fourth are free and slender, whilst the following are immovably fixed
between rings formed by the ossification of the outer membrane of the
elongate air-bladder in a manner unique among fishes. The skull is peculiar
for its very strong, denticulate, occipital crest, which ends posteriorly
in a curved spine bent forwards; the suborbitals are slender and do not
emit a subocular lamina. _Kurtus indicus_ does not exceed a length of 5
inches.
[Illustration: FIG. 419.—Skeleton of _Kurtus indicus_.]
DIVISION V.—GOBIIFORMES.
No bony stay for the praeoperculum. Basis cranii simple. Spinous dorsal, if
present, formed of few, flexible rays. None of the epipleural bones
attached to the centra of the vertebrae in the praecaudal region. Scapula
and coracoid more or less reduced or even vestigial; pterygials large, 4 or
5 in number, forming together a thin plate which is in contact with or
narrowly separated from the clavicle; one or two of the pterygials in
contact with the coracoid. Ventral fins thoracic.
The Gobiidae, which alone constitute this division, are not very remote
from the Perciformes, and may have evolved out of a type not very different
from the Percidae.
{689}FAM. 1. GOBIIDAE.—Suborbital arch ligamentous or absent.
Gill-membranes more or less broadly attached to isthmus; 4 to 6
branchiostegal rays; gills 4, a slit behind the fourth; pseudobranchiae
often present. All or most of the praecaudal vertebrae with transverse
processes bearing the ribs, to which epipleurals are attached.
Post-temporal forked, as in normal Perciformes. Ventral fins with 1 feeble
spine and 4 or 5 branched rays, often united to form a sucking disk, a
transverse fold of skin at their base completing the cup.
Head usually more or less depressed, body varying from short and stout to
elongate and eel-shaped, but never with a very high number of vertebrae,
these varying from 24 to 37 (10-14 + 13-24); scales cycloid or ctenoid, or
absent; no lateral line; mouth moderate or large, dentition various; soft
dorsal and anal fins nearly equally developed, varying from very short to
very elongate; usually a large anal papilla.
[Illustration: FIG. 420.—_Gobius ruthensparri_. Nat. size. (From Holt and
Byrne, _Report Fisheries Ireland for 1901_.)]
A large family of some 600 species, the great majority marine, mostly
carnivorous and of small size. The largest form (_Eleotris marmorata_, from
the rivers of Siam, Borneo, and Sumatra) grows to nearly 3 feet, whilst the
smallest (_Mistichthys luzonensis_, from the Philippines) measures only 12
to 14 millimetres, and is believed to be the smallest known Vertebrate.
Gobiids occur in all the seas outside the Arctic and Antarctic circles, and
they have representatives in the fresh waters of all parts of the world.
The genera are numerous but difficult of definition. The following are the
principal: _Eleotris_, _Oxymetopon_, _Vireosa_, _Rhyacichthys_, _Gobius_,
_Crystallogobius_, _Aphia_, _Gobiosoma_, _Gobiodon_, _Benthophilus_,
_Typhlogobius_, _Luciogobius_, _Sicydium_, _Lentipes_, _Periophthalmus_,
_Boleophthalmus_, _Amblyopus_, _Trypauchen_, {690}_Trypauchenichthys_.
_Oxuderces_, which has been made the type of a distinct family, appears to
differ from _Trypauchen_ only in the absence of ventral fins. Fossils
referred to _Gobius_ have been described from the Upper Eocene and Miocene
of Europe, but there is no satisfactory evidence that they really belong to
this family.
_Gobius_, of which several species are of common occurrence on our shores,
have attracted special interest from their habits during the much prolonged
breeding season. The male, usually more brilliantly coloured than the
female, mounts guard over the eggs, which are either simply fixed by the
female to the under surface of stones or weeds, or in a sort of nest built
and kept in constant repair by him. This nest is usually made of a shell of
_Cardium_, _Patella_, _Haliotis_, etc., or of the carapace of a crab, with
the convexity turned upwards and covered with sand; the sand underneath is
hollowed out, and a round opening at the side, coated by a mucus secreted
by the skin of the male fish, gives access to the interior; the eggs, which
are elongate and pyriform, are stuck to the inner surface of the shell
forming the roof.[730] A curious British form is _Aphia pellucida_, two
inches long which, from its transparent and almost colourless body, has
long been erroneously supposed to be the fry of some larger fish. Among
exotic forms, mention should be made of the Blind Goby (_Typhlogobius
californiensis_), two inches long, uniform light pink, scaleless, with the
eyes very small, reduced to mere vestiges, covered by skin, and functional
only in the young, living like a slug under rocks between tide marks on the
coast of California;[731] and to the Walking-Fish or Jumping-Fish
(_Periophthalmus_), of which various species are found in great abundance
on the mud-flats at the mouths of rivers in tropical Africa, Asia, and
North-West Australia, skipping about by means of the muscular, scaly base
of their pectoral fins, with the head raised and bearing a pair of strongly
projecting versatile eyes close together.[732]
{691}DIVISION VI.—DISCOCEPHALI.
Highly aberrant Acanthopterygians with the anterior dorsal fin modified
into a suctorial, transversely laminated oval disk[733] on the head, the
skull being very much flattened and with simple basis cranii. The pectoral
rays are inserted on the small, perforate, scapula and on four
hour-glass-shaped pterygials, three of which are in contact with the
coracoid. Ventrals thoracic.
FAM. 1. ECHENEIDIDAE.—Maxillary slender, adnate to the upper surface of the
praemaxillary; suborbital arch slender. Pectoral fin inserted high up;
supraclavicle much reduced; ventral fin with one spine and five soft rays.
Body elongate and covered with small scales; soft dorsal and anal fins
elongate and opposed to each other. All the praecaudal vertebrae with very
strong parapophyses, the anterior with diapophyses as well; ribs and
epipleurals nearly equally developed, both inserted at the extremity of the
parapophyses.
[Illustration: FIG. 421.—_Remora brachyptera_. (After Goode.) × ½.]
In spite of a superficial external resemblance to the genus _Elacate_, the
Sucking-Fish bear certainly no affinity to that genus nor to other
Scombriformes, as first observed by Gill. They are probably derived from
Perciformes, but from which family it is impossible to suggest. Three
genera may be distinguished: _Opisthomyzon_, from the Upper Eocene of
Switzerland, with a very small suctorial disk and 23 or 24 vertebrae;
_Echeneis_, with large disk and 30 vertebrae; and _Remora_, distinguished
from the second by a shorter body with only 27 vertebrae. These remarkable
fishes, of which about 10 species are distinguished, are distributed all
over the tropical and warm seas, and exceptionally carried as far north as
the south coast of England. They feed on other fishes, and attach
themselves by means of their cephalic {692}sucker to boats or to sharks,
turtles, cetaceans, and other large swift-swimming animals. On the East
Coast of Africa they are employed by the natives for catching turtles, to
the carapace of which they stick with extraordinary tenacity, being held by
a line attached to a metal ring round the caudal peduncle.[734] The largest
Sucking-fish grows to a length of three feet.
DIVISION VII.—SCLEROPAREI.
Second suborbital bone more or less produced towards or ankylosed with the
praeoperculum ("suborbital stay").[735] Ventral fins thoracic.
[Illustration: FIG. 422.—Skull of _Ophiodon elongatus_. _sor_, Suborbital
stay.]
The "Cheek-armoured Acanthopterygians," "Joues cuirassées" of Cuvier, after
the exclusion of the Sticklebacks, form a perfectly natural association,
evidently derived from the Serranidae, with which the more generalised
forms have much in common. From the Perch-like genus, _Sebastes_, a
continuous series can be traced towards the Triglidae, especially through
such forms as _Apistus_, _Minous_, and _Choridactylus_, in which one or
more of the lower pectoral rays are detached from the rest of the fin.
Through the Comephoridae the Scorpaenidae are connected with the Cottidae,
whilst the latter merge insensibly into the still more aberrant
Cyclopteridae. These conclusions, which are apparent enough from a mere
comparison of the external characters, become fortified by a study of the
skeletons. The passage between the various groups here accepted as families
is so complete that no {693}serious objection could be raised to their
union in one great family with a number of minor divisions.
[Illustration: FIG. 423.—Left pectoral arch of A, _Sebastes percoides_; B,
_Scorpaenichthys marmoratus_; C, _Dactylopterus volitans_. _cl_, Clavicle;
_cor_, coracoid; _pcl_, post-clavicle; _p.r_, pectoral rays; _ptr_,
pterygials; _ptte_, post-temporal; _sc_, scapula; _scl_, supraclavicle.]
The character from which the Scleroparei derive their name is subject to
many modifications. The second suborbital (the third if the praeorbital be
regarded as the first) may be merely enlarged and prolonged over the cheek
towards the praeoperculum (_Sebastes_, _Anoplopoma_), or firmly ankylosed
to the latter (_Scorpaena_, _Platycephalus_), or form part of the external
armature of the head (_Trigla_, _Dactylopterus_). The structure of the base
of the pectoral fin appears to afford important characters for the
definition of the families, as first pointed out by Gill; these
{694}characters have, however, not yet been tested on a sufficient number
of the very numerous forms grouped under Cottidae, some of which I have
already transferred to the Comephoridae.
SYNOPSIS OF THE FAMILIES.
I. Head not completely cuirassed.
A. Ventral fins not widely separated; none of the pectoral pterygials
in contact with the clavicle.
Two nostrils on each side; basis cranii double; gill-membranes free
from isthmus 1. _Scorpaenidae_.
A single nostril on each side; basis cranii double; gill-membranes
free from isthmus 2. _Hexagrammidae_.
Two nostrils on each side; basis cranii simple; gill-membranes free
or narrowly attached to isthmus 3. _Comephoridae_.
Two nostrils on each side; basis cranii simple; gill-opening
narrow, above base of pectoral 4. _Rhamphocottidae_.
B. Ventral fins, if present, not widely separated; one or several of
the pterygials in contact with the clavicle.
Ventral fins distinct; gill-clefts wide 5. _Cottidae_.
Ventral fins united into a sucking disk; gill-opening narrow, above
base of pectoral 6. _Cyclopteridae_.
C. Ventral fins widely separated; none of the pterygials in contact
with the clavicle.
Ventral fins behind base of pectorals; praecaudal vertebrae without
transverse processes 7. _Platycephalidae_.
Ventral fins a little in front of base of pectorals; praecaudal
vertebrae with transverse processes 8. _Hoplichthyidae_.
II. Head completely cuirassed.
Ventral fins narrowly separated; no pectoral appendages; pterygials
short and broad 9. _Agonidae_.
Ventral fins widely separated; 2 or 3 lowermost rays of pectoral
fin detached as feelers; pterygials short and broad
10. _Triglidae_.
Ventral fins narrowly separated; pectoral fin divided into two
portions; pterygials elongate 11. _Dactylopteridae_.
FAM. 1. SCORPAENIDAE.—Head not or but incompletely cuirassed, usually with
spines; basis cranii double; parietal bones often meeting on the median
line, over the supraoccipital; two nostrils on each side. Gill-membranes
free from isthmus; gills 3½ or 4; pseudobranchiae present. Vertebrae 24 to
37, the anterior praecaudals with sessile ribs bearing epipleurals, the
posterior with transverse processes, often directed downwards, or forming
haemal arches, bearing the rib and the epipleural. Post-temporal more or
less distinctly forked, more or less firmly ankylosed to the skull; scapula
and coracoid well developed, in contact with each other or separated by
cartilage; pectoral rays inserted {695}on the scapula and on 3 or 4 large,
hour-glass or anvil-shaped pterygials, two of which are in contact with the
coracoid. Ventral fins close together, with 1 spine and 3 to 5 soft rays.
Spinous dorsal strong, usually longer than the soft, sometimes extending on
the head; anal usually with 3 spines. Body covered with scales or naked.
A large family of carnivorous marine fishes, some descending to great
depths, of nearly world-wide distribution, represented by three extinct
genera (_Ampheristus_, _Histiocephalus_, _Scorpaenoides_) in the Eocene and
by several species of _Scorpaena_ in later formations. About 250 recent
species are known. Principal genera: _Sebastes_, _Setarches_, _Scorpaena_,
_Pterois_, _Apistus_, _Minous_, _Pelor_, _Choridactylus_, _Centropogon_,
_Gymnapistus_, _Amblyapistus_, _Pentaroge_, _Tetraroge_, _Gnathacanthus_
(_Holoxenus_), _Agriopus_, _Synancia_, _Polycaulus_.
[Illustration: FIG. 424.—_Scorpaena grandicornis_. (After Valenciennes.) ×
½.]
Great variety of form obtains in this family, from the Perch-like
_Sebastes_ to the extraordinary-shaped _Tetraroge_, _Pelor_, and
_Synancia_. Many of its members are excellent examples of mimetic
adaptation to the surrounding, resembling the rocks among which they live
and being covered with dermal appendages simulating weeds. An interesting
example of commensalism has been discovered by A. Alcock[736] in _Minous
inermis_, off the coasts of India, which, wherever found, is always more or
less incrusted with the {696}Gymnoblastic Hydroid _Stylactis minoi_. Many
of the _Sebastes_ and their allies are of large size and used as food; some
are viviparous, the young being produced in great numbers and very small in
size. _Scorpaena_, _Pterois_, _Pelor_, and _Synancia_ are dangerous for the
stings from their dorsal spines, which are provided with poison
glands.[737]
FAM. 2. HEXAGRAMMIDAE.—Head not cuirassed, without strong spines; basis
cranii double; a single nostril on each side. Gill-membranes free from
isthmus; gills 4; pseudobranchiae present. Vertebrae 42 to 57, most of the
praecaudals with transverse processes bearing the ribs and the epipleurals.
Post-temporal forked; scapula and coracoid well developed, in contact with
each other; pectoral rays inserted on the scapula and 4 anvil-shaped
pterygials, 2 of which are in contact with the coracoid. Ventral fins close
together, more or less behind the pectorals, with 1 spine and 5 soft rays.
Spinous dorsal of usually rather feeble rays, nearly as long as or longer
than the soft; anal elongate, with or without spines. Body covered with
small scales.
Carnivorous fishes, mostly of large size, from the rocky coasts of the
North Pacific. Some are highly valued as food. Twelve species, referable to
6 genera: _Hexagrammus_, _Pleurogrammus_, _Agrammus_, _Ophiodon_,
_Zaniolepis_, _Oxylebius_. _Hexagrammus_ and _Pleurogrammus_ are remarkable
in having 4 or 5 lateral lines on each side.
FAM. 3. COMEPHORIDAE.—Head not cuirassed, without spines; basis cranii
simple; two nostrils on each side. Gill-membranes free or narrowly attached
to isthmus; gills 4; pseudobranchiae present or absent. Vertebrae 42 to 64,
some or most of the praecaudals with transverse processes bearing the ribs
and the epipleurals. Post-temporal forked; scapula and coracoid well
developed, in contact with each other or separated by cartilage; pectoral
rays inserted on the scapula and on 4 anvil-shaped or plate-like
pterygials, 2 of which are in contact with the coracoid. Ventral fins, if
present, close together, with 1 spine and 3 to 5 soft rays. Spinous dorsal
of rather feeble rays, as long as or shorter than the soft; anal spines
feeble or absent. Body covered with small scales or naked.
{697}Four genera, each with a single species: _Anoplopoma_
(_Scombrocottus_), from the North Pacific from Unalaska to California;
_Triglopsis_, from deep water in Lakes Michigan and Ontario;
_Cottocomephorus_, from Lake Baikal, and _Comephorus_ from the greatest
depths of that lake. As in many bathybial forms, _Comephorus_ is colourless
and provided with very large eyes; ventral fins are absent and the skeleton
is very thin and papery. As a result of this condition, the second
suborbital is not produced over the cheek, a unique exception to the main
characteristic of this division; but no doubt can be entertained as to the
propriety of referring it to the neighbourhood of _Anoplopoma_, since the
recently discovered _Cottocomephorus_ may be regarded as a connecting link
between the two genera. _Comephorus_ is viviparous, and dies after
parturition.[738] Jordan regards _Triglopsis_ as a relic of a former Arctic
marine fauna.
FAM. 4. RHAMPHOCOTTIDAE.—Head incompletely cuirassed, with spines; basis
cranii simple; two nostrils on each side. Gill-opening narrow, above the
base of the pectoral; gills 3½. Vertebrae 24. Post-temporal short and flat,
ankylosed to the skull; scapula and coracoid well developed, separated by
cartilage; pectoral rays inserted on the scapula and on 4 plate-like
pterygials, 2 of which are in contact with the coracoid. Ventral fins close
together, behind the pectorals, with a rudimentary spine and 3 soft rays.
Spinous dorsal shorter than the soft; no anal spines. Body densely covered
with small prickly scales.
_Rhamphocottus richardsonii_, a small fish 3 inches in length, from the
north-west coast of North America, is the only representative of this
family.
FAM. 5. COTTIDAE.—Head not or but incompletely cuirassed, usually with
spines; basis cranii simple; parietal bones often meeting on the median
line; two nostrils on each side. Gill-membranes free or attached to
isthmus; gills 3½ or 4; pseudobranchiae usually present. Vertebrae 24 to
50, the anterior praecaudals with sessile ribs, the posterior with
transverse processes, often directed downwards, or forming haemal arches,
bearing ribs and epipleurals. Post-temporal more or less distinctly forked;
scapula and coracoid separated from each other {698}by the intervention of
the plate-like pterygials, of which one, two, or three are in contact with
the clavicle; the coracoid more or less reduced. Ventral fins close
together, with 1 spine and 2 to 5 soft rays (absent in _Ereunias_). Spinous
dorsal usually shorter than the soft, sometimes quite indistinct; anal
without spines. Body naked, partially scaly, or with prickles or bony
plates.
Mostly small carnivorous fishes, the largest (_Scorpaenichthys_) growing to
about 3 feet. Some species inhabit fresh waters, but the majority are
marine, a few descending to great depths. Nearly all are from the northern
regions, but a genus allied to _Cottus_ (_Sclerocottus_) is from South
Georgia, in the Antarctic region. Fossil Cottidae are known from the Upper
Eocene and Miocene (_Eocottus_, _Lepidocottus_), and are distinguished from
the modern forms in the smaller number of vertebrae (24 or 26 instead of 30
to 50). At least 220 species are known. Principal genera: _Jordania_,
_Scorpaenichthys_, _Icelus_, _Triglops_, _Cottus_, _Cottunculus_,
_Blepsias_, _Pseudoblennius_, _Hemitripterus_, _Synchirus_, _Ascelichthys_,
_Psychrolutes_, _Ereunias_. The little freshwater "Miller's Thumb" (_Cottus
gobio_) and the larger marine "Bull-heads" (_C. bubalis_ and _C. scorpius_)
are the most familiar British representatives of this family. The eggs are
deposited on stones, weeds, or other submerged objects, or in a sort of
nest, and are guarded by the male, which in most species is distinguished
by a large genital papilla; this, in some forms, acts as an intromittent
organ.
FAM. 6. CYCLOPTERIDAE.—Very closely related to the preceding, with which
they are connected through _Psychrolutes_, and it is even doubtful whether
they deserve to be separated from them. The only important distinctive
characters reside in the structure of the ventrals, which, if present
(absent in _Paraliparis_, a close ally of _Liparis_), are united to form a
sucking disk, and the small size of the gill-cleft. The body is short,
tumid, tadpole-like, naked or tubercular; the spinous dorsal, if present,
is short. Vertebrae 28 to 60, the skeleton feebly ossified.[739]
Sluggish fishes, feeding on small animals and plants, from the North
Atlantic and Pacific Oceans, and the Arctic and Antarctic seas, many
descending to great depths (1800 fathoms). About fifty species are
distinguished. Principal genera: _Cyclopterus_, _Cyclopterichthys_,
_Liparops_, _Liparis_, _Careproctus_, _Paraliparis_.
{699}The common Lump-Sucker of our coasts (_Cyclopterus lumpus_) is the
largest member of the group, growing to a length of 2 feet or more. The
male makes pits in the sand between stones, in which the female deposits
the eggs; he watches over the eggs and also over the young, which cling to
his body with their suckers. The "Sea-Snails" (_Liparis_), are represented
by two species on the British coasts.
[Illustration: FIG. 425.—_Cyclopterus lumpus_. × ⅓.]
FAM. 7. PLATYCEPHALIDAE.—Head not cuirassed, much depressed, with spines;
basis cranii simple; two nostrils on each side. Gill-membranes free; gills
4; pseudobranchiae present. Vertebrae 27; ribs all sessile, bearing the
epipleurals. Post-temporal forked; scapula and coracoid well developed, in
contact with each other; pectoral rays inserted on the scapula and on 4
short and broad pterygials, 2 of which are in contact with the coracoid.
Ventral fins widely separated, behind the pectorals, with 1 spine and 5
soft rays. Spinous dorsal shorter than the soft; anal without spines. Body
covered with small scales.
The single genus _Platycephalus_, with some 40 species, inhabits the coasts
of the Indian Ocean and the Western Pacific.
FAM. 8. HOPLICHTHYIDAE.—Head incompletely cuirassed, much depressed, with
spines; basis cranii simple; two nostrils on each side. Gill-membranes
attached to isthmus; gills 4; pseudobranchiae present. Vertebrae about 30,
the praecaudals with transverse processes. Post-temporal fused with the
skull; scapula and coracoid in contact with each other; pectoral rays
inserted on the scapula and on 3 plate-like pterygials. Ventral fins widely
separated, a little before the pectorals, with 1 spine and 5 soft
{700}rays. Spinous dorsal shorter than the soft; anal without spines. Back
and sides with bony, prickly plates.
_Hoplichthys_, with a single species from the coasts of Japan and China.
_Bembras_, with two species from the coasts of Japan, appears to be related
to it, but the skeleton is still unknown; it differs in having the body
covered with small scales and the gill-membranes free.
FAM. 9. AGONIDAE.—Head completely cuirassed, usually with spines; basis
cranii simple; two nostrils on each side. Gill-membranes free or attached
to isthmus; gills 3½; pseudobranchiae present. Vertebrae 35 to 50; ribs
sessile. Post-temporal fused with the skull; scapula and coracoid in
contact with each other, or separated by a cartilaginous space; pectoral
rays inserted on the scapula and 3 or 4 plate-like pterygials. Ventral fins
close together, with 1 spine and 2 soft rays. Spinous dorsal shorter than
the soft, or absent; anal without spines. Body covered with bony plates.
Small fishes, mostly from the coasts of the Northern Atlantic and Pacific,
extending into the Arctic Ocean; one species from the coast of Chili.
_Bathyagonus_ occurs in the North Atlantic between 350 and 477 fathoms.
About 40 species are known. Principal genera: _Agonus_, _Agonopsis_,
_Bathyagonus_, _Aspidophoroides_. The "Pogge," or Armed Bullhead (_Agonus
cataphractus_), is the only British species of this family.
FAM. 10. TRIGLIDAE.—Head completely cuirassed, with spines; basis cranii
double; parietal bones meeting on the median line; two nostrils on each
side. Gill-membranes free; gills 4; pseudobranchiae present. Vertebrae 25
to 40, the anterior praecaudals with sessile ribs, the posterior with
transverse processes. Post-temporal fused with the skull; scapula and
coracoid separated by a cartilaginous space; pectoral rays inserted on the
scapula and on 4 large plate-like pterygials, of which two are in contact
with the coracoid; 2 or 3 of the lower pectoral rays detached, forming
feelers. Ventral fins widely separated, with 1 spine and 5 soft rays.
Spinous dorsal shorter than the soft; anal without spines. Body covered
with scales or bony plates.
Marine fishes from all warm and temperate regions, some occurring in deep
water. They are remarkable for the {701}finger-like appendages of the
pectoral fins, which are employed to feel the ground in search of
crustaceans and other small animals on which they feed; also for the
grunting sounds which they utter by the contraction of the air-bladder.
About 50 species are known, referable to 4 genera: _Prionotus_, _Trigla_,
_Lepidotrigla_, _Peristedion_. Fossil remains referred to _Trigla_ have
been found in Miocene and later formations. British species are the Grey
Gurnard (_Trigla gurnardus_), the Red Gurnard (_T. cuculus_), the Tub or
Sapphirine Gurnard (_T. hirundo_), the Piper (_T. lyra_), the Long-finned
Gurnard (_T. obscura_), and the Streaked Gurnard (_T. lineata_).
[Illustration: FIG. 426.—_Dactylopterus volitans_. (After Gill.) ⅓ nat.
size.]
FAM. 11. DACTYLOPTERIDAE.—Head completely cuirassed; basis cranii simple;
parietal bones meeting on the median line; two nostrils on each side.
Gill-cleft broadly separated by scaly isthmus; gills 4; pseudobranchiae
present. Vertebrae 20-22 (8-9 + 12-13), the first very elongate and formed
by the fusion of three or four; ribs sessile, no transverse processes.
Post-temporal fused with the skull; no supraclavicle; scapula and coracoid
well developed, in contact with each other; pectoral rays divided into two
parts, inserted on the scapula and on 4 elongate pterygials, of which 3 are
in contact with the coracoid. Ventral fins close together, with 1 spine and
4 soft rays. Spinous dorsal shorter than the soft; anal without spines.
Body covered with hard, rough scales.
The "Flying Gurnards," of which four species are known, belonging to a
single genus (_Dactylopterus_), are inhabitants of the tropical and warm
parts of the Atlantic and the Indian Ocean and Archipelago. They are
remarkable, when adult, for the {702}wing-like portion of the pectoral
fins, by which they are able to move in the air like _Exocoetus_, but for
shorter distances, and, unlike them, the wings are moved rapidly, the mode
of flight resembling that of many forms of grasshoppers;[740] the young,
however, have comparatively short pectorals, and were formerly regarded as
belonging to a distinct genus (_Cephalacanthus_).
DIVISION VIII.—JUGULARES.
No bony stay for the praeoperculum. Ventral fins jugular or mental.
Gill-openings in front of the pectoral fin, the base of which is vertical
or subvertical.
In a recently published note[741] I have alluded to the group of
Physoclistous fishes for which I proposed to revive the old name Jugulares,
pointing out that some of the forms previously grouped together as
Trachinidae agree with the Gadidae, not only in the jugular position of the
ventral fins, but also in the condition of the scapula and coracoid. Mr.
Regan[742] has since been able to show that the Gadidae and Macruridae
possess certain characters in common by which they may be separated not
only from the other Jugulares, but even from the Acanthopterygians, and, as
mentioned above (p. 646), the Müllerian Sub-order Anacanthini may be
maintained, after excluding the Pleuronectidae. That the Blenniidae are
akin to _Lycodes_ and its allies has long been admitted, and authors who
have placed them in different divisions of their systems have had to
confess the difficulty of referring certain genera to the one family rather
than to the other. The fact that _Lycodes_ and many forms previously
associated with the Ophidiidae agree with the Macruridae and Gadidae in the
diphycercal vertebral column and in the absence of spines to the fins is
merely, it seems to me, the result of degradation; they probably form the
terminal group of a series in which the vertebral column was originally
homocercal and fin-spines were present, as is the case in most of the
Blenniidae and Trachinidae and their near allies. All these families may be
assumed to have evolved in several series, often on parallel lines, from
some group closely related to the {703}Berycidae; and the resemblance which
their terminal forms bear to the Anacanthini is, as pointed out by Regan,
probably to be ascribed to convergence, not to any close genetic affinity,
as hitherto believed by many authors.
[Illustration: FIG. 427.—Pectoral arch and pelvis (left side) of A,
_Trachinus draco_; B, _Percophis brasilianus_; _cl_, clavicle; _cor_,
coracoid; _pelv_, pelvis; _pt_, pterygials; _ptcl_, post-clavicle; _pte_,
post-temporal; _sc_, scapula; _scl_, supraclavicle.]
The character of the position of the scapular foramen, either in the
scapular bone or between it and the coracoid, which obtains in many genera
of this division as well as in most of the Anacanthini, has proved to be
unreliable even for the purpose of family definition; it is, however, of
assistance in determining the relation of certain obscure, degraded forms
placed by some authors with the Anacanthines, by others with the Blenniids.
SYNOPSIS OF THE FAMILIES.
I. Pectoral rays attached to the scapula and to a series of pterygials
of which only one or two are in contact with the scapula (see
Fig. 427); ventral fins jugular, with 1 spine and 4 or 5 soft rays;
anterior dorsal rays usually spinous or not articulated, often forming
a detached fin.
A. Epipleurals present.
1. Second suborbital produced inwards to support the eye-ball.
Ventrals close together; scales very small, cycloid, forming
oblique bands 1. _Trachinidae_.
Ventrals widely separated 2. _Percophiidae_.
2. No subocular shelf.
Ventrals widely separated; two nostrils on each side
3. _Leptoscopidae_.
Ventrals widely separated; a single nostril on each side
4. _Nototheniidae_.
Ventrals close together; scales very small, forming oblique bands;
head partly covered with bony plates 5. _Uranoscopidae_.
B. No epipleurals. {704}
Post-temporal forked, articulated to the skull; soft dorsal and anal
much elongate 6. _Trichodontidae_.
Post-temporal closely adnate to the skull; soft dorsal and anal
short (with only 7 to 10 rays) 7. _Callionymidae_.
Post-temporal simple, articulated to the skull; soft dorsal and anal
short; a ventral sucker 8. _Gobiesocidae_.
II. Pectoral rays all attached to the pterygials, of which two or three
are in contact with the scapula; ventral fins, if present, jugular or
mental, composed of 1 to 4 rays.
A. Ventrals jugular or absent.
Post-temporal distinctly forked; praecaudal vertebrae with
transverse processes; some or all of the dorsal rays spinous
or not articulated; caudal fin usually distinct 9. _Blenniidae_.
Post-temporal small and ankylosed to the skull; praecaudal
vertebrae without well-developed transverse processes; a very
short spinous dorsal; caudal fin distinct 10. _Batrachidae_.
Post-temporal distinctly forked; praecaudal vertebrae with haemal
arches; dorsal rays all spinous; caudal fin distinct
11. _Pholididae_.
Post-temporal distinctly forked; praecaudal vertebrae with
transverse processes; dorsal rays all articulated, or a few of
the posterior spinous; no distinct caudal fin 12. _Zoarcidae_.
Post-temporal forked, ankylosed to the skull; praecaudal vertebrae
with transverse processes; no spines; no distinct caudal fin
13. _Congrogadidae_
B. Ventrals mental (just behind the chin); no spines 14. _Ophidiidae_.
III. Pectoral rays attached to an undivided cartilaginous plate
representing the pterygials; ventral fins jugular, reduced to a
filament formed of two adnate rays; fins without spines
15. _Podatelidae_.
FAM. 1. TRACHINIDAE.—Second suborbital with an internal lamina, supporting
the globe of the eye; mouth large, protractile. Ribs and epipleurals nearly
equally developed, sessile; posterior praecaudal vertebrae with short
parapophyses. Gill-membranes free from isthmus; 6 branchiostegal rays;
gills 4, a slit behind the fourth; pseudobranchiae well developed. Scapula
and coracoid well developed, a foramen between them; pectoral rays attached
to the scapula and to three short and broad pterygials, two of which are in
contact with the coracoid. Ventral fins jugular, close together, with 1
spine and 5 soft rays. Body elongate, covered with small cycloid scales
forming oblique bands. A short spinous dorsal and a long soft dorsal and
anal. Vertebrae 35-43 (10-11 + 25-32). No air-bladder.
This family includes but one genus (_Trachinus_), the Weevers, with 4
species, occurring on the coasts of Europe, the {705}Mediterranean, and
West Africa north of the Equator. A fossil species has been described from
the Upper Miocene of Croatia. The two British species, _T. draco_ and _T.
vipera_, are well known for the painful wounds which they are able to
inflict through their sharp, grooved dorsal and opercular spines, which
convey a very active poisonous fluid secreted by small glands at their
base. As these fish like to bury themselves partially in the sands in
shallow water, people bathing occasionally tread on them with, as a rule,
at least violent pain as a result.[743] The flesh is not bad eating, and
great numbers of the larger species (_T. draco_), are brought to the Paris
market.
FAM. 2. PERCOPHIIDAE.—_Percophis_, with a single species from the coast of
Brazil, differs from the Trachinidae in the scapular fenestra being
situated entirely in the scapula, in the ventral fins being rather widely
separated at the base, and in the quincuncial disposition of the scales.
Vertebrae, 57 (22 + 35). _Bleekeria_ and _Embolichthys_, from the Indian
and Japanese seas, with the ventral fins rudimentary or absent, which have
been placed in the Ammodytidae, appear to be related to _Percophis_.
FAM. 3. LEPTOSCOPIDAE.—Differ from the preceding in the absence of a
subocular shelf. Scapular fenestra either in the scapula or between the
scapula and the coracoid. Mostly Marine Fishes, various in form, from the
tropics to the Antarctic circle, some occurring at great depths. About 25
species, referable to 7 genera: _Leptoscopus_, _Parapercis_, _Neopercis_,
_Pteropsaron_, _Bembrops_, _Pleuragramma_, _Chimarrhichthys_. The latter,
from New Zealand, is the only freshwater form of the family, and is
remarkably adapted for living in alpine torrents. _Pleuragramma
antarcticum_, brought home by the Southern Cross Expedition, comes from 78°
35´ S. lat., the farthest point at which fishes have yet been obtained in
the Antarctic region. _Macrius amissus_, from the Pacific Ocean at a depth
of 1000 fathoms, which, judging from a very imperfect description, probably
belongs to this family, measures 5 feet, and is the largest known deep-sea
Teleostean.
FAM. 4. NOTOTHENIIDAE.—Also closely allied to the Trachinidae. No subocular
shelf; a single nostril on each side; ventrals {706}widely separated;
pectoral arch usually as in the Trachinidae, but scapular fenestra
sometimes in the scapula (_Trematomus_). Body varying much in shape
according to the genera, the form sometimes suggestive of the Cottidae;
scales usually ctenoid, sometimes absent; anterior (spinous) dorsal
sometimes absent; lateral line often double, or even triple. Mostly from
the Southern seas and the Antarctic circle. About 40 species, referable to
19 genera, of which the following are the principal:—_Notothenia_,
_Trematomus_, _Chaenichthys_, _Champsocephalus_, _Cryodraco_,
_Acanthaphritis_, _Eleginops_, _Bovichthys_, _Gymnodraco_, _Gerlachia_,
_Bathydraco_, _Racovitzaia_, _Harpagifer_, _Draconetta_.
FAM. 5. URANOSCOPIDAE.—Agree with the Trachinidae in general structure, and
in the closely approximated ventrals. Scales very small, in oblique bands,
or absent. Pterygials much reduced, fused with the scapula and the
coracoid; scapular fenestra in the scapula. Parapophyses strongly developed
on the praecaudal vertebrae, with the ribs attached to their upper surface.
The head is very large, broad, partly covered with bony plates; cleft of
the mouth vertical; eyes on the upper surface of the head. Vertebrae 25 to
30 (12-14 + 13-16). Four genera: _Uranoscopus_, _Anema_, _Cathetostoma_,
_Ariscopus_, with 15 species, from the tropical seas, northwards to the
Mediterranean and Japan, southwards to South Australia and New Zealand.
FAM. 6. TRICHONOTIDAE.—Small elongate fishes very nearly related to the
Callionymidae, with which they agree in the arrangement of the bones at the
base of the pectoral fins and the absence of epipleurals; but post-temporal
more distinctly forked and detached from the skull, suborbital arch
ossified (without subocular shelf), gill-openings wide, a single long
dorsal fin, a long anal fin, and body covered with scales. Vertebrae 48-53.
Five marine species, referable to 3 genera: _Trichonotus_ and
_Taeniolabrus_ from the Indian Ocean, and _Hemerocoetes_ from New Zealand.
FAM. 7. CALLIONYMIDAE.—Suborbital arch ligamentous; entopterygoid absent;
basis cranii simple; mouth rather small, protractile. Vertebrae few (7 +
14), the last two much enlarged; most of the vertebrae with bifid neural
processes, simulating a "spina bifida"; first vertebra ribless,[744] second
to fourth {707}with sessile ribs and no transverse processes, fifth to
seventh with ribs inserted on short transverse processes; no epipleurals.
Post-temporal forked, but completely adnate to the skull; scapula separated
from the coracoid by a fenestra; pectoral rays attached to the scapula and
to three broad pterygials, all three in contact with the coracoid. Ventral
fins jugular, widely separated from each other, with 5 soft rays in
addition to a short spine. Gill-openings very narrow, generally reduced to
a foramen on the upper side of the operculum; 6 branchiostegal rays; gills
4, a slit behind the fourth; pseudobranchiae well developed. Body naked.
Two dorsal fins, the first composed of a few flexible spines; second dorsal
and anal rather short (7-10 rays).
Small marine fishes, referable to 2 genera; _Callionymus_, with about 45
species, nearly cosmopolitan, and _Vulsus_, with a single species from
Amboyna and Celebes. In the common British species, the Dragonet
(_Callionymus lyra_), the male acquires very marked secondary characters,
the snout becoming more elongate, the second dorsal fin much produced, and
the body ornamented with yellow and blue bands. The courtship and pairing
have been described by E. W. L. Holt,[745] who observes that this curious
fish offers the only instance of a definite sexual intercourse among
Teleosteans propagating by pelagic ova. In the Indian _C. carebares_ it is
the female that is the more brightly coloured.
FAM. 8. GOBIESOCIDAE.—Suborbital arch absent; entopterygoid absent; basis
cranii simple; mouth moderate, protractile. Vertebrae numerous, 27-31
(14-16 + 11-21), the first, if present, rudimentary,[746] the third and
following praecaudals with long parapophyses[747] bearing the ribs at their
extremity; no epipleurals. Post-temporal simple, articulated to the skull;
scapula with a foramen, coracoid much reduced; pectoral rays inserted on
the scapula and on four large pterygials, two of which are in contact with
the scapula; an adhesive ventral disk, simple or double, supported in front
by the clavicles, in the {708}middle and at the sides by the enlarged
pelvic bones and fins, and behind by the enlarged lamellar post-clavicles,
which are formed of two pieces. Ventral fins jugular, widely separated from
each other, formed of 1 short spine and 4 or 5 soft rays. Gill-openings
narrow; 5 or 6 branchiostegal rays; gills 3 or 3½; pseudobranchiae well
developed. Body naked. Dorsal and anal fins short, composed entirely of
soft branched rays.
First placed with the Acanthopterygians by J. Müller, notwithstanding the
absence of spinous rays in the vertical fins, and removed from the vicinity
of the Cyclopteridae by Günther, raised to the rank of a Sub-order
(Xenopteri) near the Anacanthini by Gill, the exact systematic position of
this curious type of Fishes has long been a matter of uncertainty. The
position of the ventral fins suggests, at first glance, affinity with the
Callionymidae, and a comparison of the skeletons of these two types has
convinced me that they are really related to each other, although both
highly modified in different directions.
[Illustration: FIG. 428.—_Sicyases sanguineus_, natural size. _a_, Anus;
_op_, opercle; _pf_, pectoral fin.]
The Cling-Fishes are curious small, carnivorous, Marine Fishes, usually
found between tide-marks among loose stones and shells, to which they
adhere firmly by means of the adhesive ventral disk. They can live a long
time out of water. About 50 species are known, from various parts of the
world, extending as far north as Scotland and Vancouver Island, and
southwards to {709}New Zealand. Three or four species, belonging to the
genus _Lepadogaster_, are known to occur on the British coasts. The
principal genera are _Gobiesox_, _Chorisochismus_, _Sicyases_, _Cotylis_,
_Lepadogaster_, _Trachelochismus_, _Diplocrepis_, _Crepidogaster_, and
_Leptopterygius_.[748]
FAM. 9. BLENNIIDAE.—Suborbitals often forming a more or less distinct
subocular shelf; mouth moderate or large, more or less protractile, often
bordered to a considerable extent by the maxillaries. Most of the
praecaudal vertebrae with strong transverse processes supporting the ribs,
which may bear epipleurals. Gill-membranes usually attached to isthmus; 6
or 7 branchiostegal rays; gills 4, a slit behind the fourth;
pseudobranchiae usually present. Post-temporal forked; scapula and coracoid
more or less developed, sometimes much reduced, the former pierced by a
foramen; pectoral rays attached to 4 or 5 hour-glass-shaped pterygials, one
or two of which are in contact with the coracoid. Ventral fins jugular,
with not more than 4 rays, or absent. Body more or less elongate, sometimes
Eel-shaped, naked or with small scales. Dorsal and anal fins elongate, the
former constituted entirely of spines, or anteriorly of spines or
non-articulated rays, and posteriorly of soft rays. Caudal fin usually
distinct, with expanded hypural.
A large family, mostly of small Marine Fishes, the arrangement of which
still offers great difficulties. Whether the aberrant genera _Cerdale_ and
_Ptilichthys_ deserve to be regarded as the types of distinct families
cannot be decided until the skeleton has been examined. The species number
about 350, from nearly all the seas, a few inhabiting fresh waters, and are
referred to numerous genera, of which the following are the
principal:—_Gadopsis_, _Enneanectes_, _Heterostichus_, _Acanthoclinus_,
_Clinus_, _Emmnion_, _Blennius_, _Chasmodes_, _Petroscirtes_, _Xiphasia_,
_Anarrhichas_, _Pataecus_, _Salarias_, _Ophioblennius_, _Anoplarchus_,
_Xiphistes_, _Opisthocentrus_, _Chaenopsis_, _Pholedichthys_, _Lumpenus_.
Remains of _Clinus_ and _Blennius_ have been described from the Miocene,
and the extinct genus _Pterygocephalus_, from the Upper Eocene, is regarded
as allied to _Clinus_.
The Blenniidae are mostly carnivorous, but a few are herbivorous; some are
viviparous (_Clinus_), others oviparous. Species {710}of _Blennius_ occur
in abundance on our coasts, and are among the most familiar tenants of
small rock-pools. Their habits have been admirably described by
Guitel.[749] The male makes a sort of nest, and defends the brood. Numerous
species of the genus _Salarias_ occur in the tropics; these little fish, as
their name implies, are remarkable for the long leaps they are able to
make. The largest of the Blenniids are the "Wolf-Fishes," often named
"Cat-Fishes" (_Anarrhichas_), of which one species (_A. lupus_) is common
on the British coasts, growing to a length of 5 or 6 feet. "It is
impossible," says Brown Goode, "to imagine a more voracious-looking animal
than the Sea Cat-Fish, with the massive head and long sinuous, muscular
body, its strongly rayed fins, its vice-like jaws, armed with great
pavements of teeth, those in front long, strong, pointed, like those of a
tiger. It has been known to attack furiously persons wading at low tide
among the rock-pools." Its flesh is excellent eating, but generally
despised in this country owing to the unprepossessing appearance of the
animal.
FAM. 10. BATRACHIDAE.—Suborbital arch absent; basis cranii simple; mouth
very large, slightly protractile, bordered to a great extent by the
maxillaries. Vertebrae numerous, 29-46 (11-12 + 17-34), without ribs, with
sessile epipleurals, simulating ribs;[750] parapophyses rudimentary or
absent. Post-temporal small and ankylosed to the skull; scapula and
coracoid much reduced, 4 or 5 elongate pterygials, dilated distally, the
two lower in contact with the coracoid. Ventral fins jugular, with 1 spine
and 2 or 3 branched rays. Gill-openings narrow, the gill-membranes broadly
grown to the isthmus; gills 3; pseudobranchiae absent. Head broad and
depressed; body naked or with small scales. Spinous dorsal very short, soft
dorsal and anal long.
This family is on the whole intermediate between the Blenniidae and the
Pediculati. Sluggish, voracious, carnivorous Fishes from the shores of
tropical and warm seas, some of them ascending rivers. The species number
about 20, referable to {711}5 genera: _Batrachus_, _Opsanus_,
_Thalassophryne_, _Thalassothia_, and _Porichthys_. The eggs of _Batrachus
tau_ are very large, ¼ inch in diameter, and are deposited in a little
retreat provided by the parent; the male assumes the care of the brood; the
young fasten themselves to rocks by means of an adhesive ventral disk,
which soon disappears.[751]
In _Thalassophryne_, from the coasts of Central America, the opercular
spine and the two dorsal spines are perforated, and convey poison from
subcutaneous sacs situated at their base.[752] In the American genus
_Porichthys_ the head and body bear series of greatly developed mucous
pores, some of which simulate the photophores of _Scopelus_, but are not
luminous.[753]
[Illustration: FIG. 429.—_Porichthys porosissimus_. (After Goode and Bean.)
½ nat. size.]
FAM. 11. PHOLIDIDAE.—Suborbitals not forming a subocular shelf; mouth
scarcely protractile, with thick lips. Praecaudal vertebrae similar to the
caudals, without transverse processes, with hæmal arches; ribs sessile.
Gill-membranes free from the isthmus; 4 or 5 branchiostegal rays; gills 4,
a slit behind the fourth; pseudobranchiae present. Scapular arch as in
Blenniidae. Ventral fins jugular and rudimentary, or absent. Body elongate,
compressed, with very small scales. Dorsal and anal fins elongate, the
former constituted entirely of non-articulated rays or spines. Caudal fin
distinct, with expanded hypuraL.
Small shore fishes of the Northern Seas, differing from the Blenniidae in
the structure of the praecaudal vertebrae, in spite of the external
resemblance which the two known genera, _Pholis_ (_Centronotus_) and
_Apodichthys_, bears to _Anoplarchus_ and _Xiphistes_. Species about 10.
{712}A well-known British fish of this family is the little Gunnel or
Butter-Fish (_Pholis gunnellus_), remarkable for the manner in which the
female protects her offspring, coiling herself round the eggs, which she
rolls up into a ball about the size of a Brazil nut, in holes of the boring
Mollusc (_Pholas_). The male sometimes assists the female.
FAM. 12. ZOARCIDAE.—Suborbitals not forming a subocular shelf; mouth feebly
protractile. Praecaudal vertebrae with strong transverse processes bearing
ribs and epipleurals. Gill-membranes usually more or less broadly united to
isthmus; 5 to 8 branchiostegal rays; gills 4, a slit behind the fourth;
pseudobranchiae present or absent. Scapular arch as in Blenniidae. Ventral
fins jugular or absent; if present, with 1 to 4 rays. Body more or less
elongate, naked or with very small scales. Dorsal and anal fins elongate,
all the rays articulated, or a few of the posterior dorsals spinous.
Usually no distinct caudal fin.
[Illustration: FIG. 430.—_Typhlonus nasus_ × ½. (After Güther.)]
These fishes have usually been placed, in part at least, near the Gadids,
but they have more in common with the Blenniids, as pointed out by Jordan
and Evermann, and may be regarded as degraded forms descended from the
latter.[754] The family is widely distributed in all seas, many of the
forms being specially adapted to live at great depths. The species known
number about 130. Principal genera: _Scytalina_, _Zoarces_, _Lycodes_,
_Gymnelis_, _Lycocara_, _Melanostigma_, _Derepodichthys_, _Bathyonus_,
_Porogadus_, _Bythitis_, _Neobythitis_, _Cataetyx_, _Selachophidium_,
_Acanthonus_, _Typhlonus_, _Aphyonus_, _Tauredophidium_, _Rhodichthys_,
_Brosmophycis_, _Brotula_, _Lucifuga_, _Lamprogrammus_, _Diplacanthopoma_,
_Hephthocara_.
{713}Some are oviparous, others (_Zoarces_, _Diplacanthopoma_,
_Hephthocara_, _Lucifuga_) viviparous. The eyes are absent, or at least not
visible externally in some of the bathybial forms (_Typhlonus_, _Aphyonus_,
_Tauredophidium_), as well as in the only known freshwater forms, the Cuban
Cave-Fishes _Stygicola_ and _Lucifuga_, which are evidently allied to the
marine _Brotula_, whilst the blind Cave-Fishes of North America (cf. p.
618) are derived from freshwater types. It is believed that blind fishes
are found also in caves of the island of Jamaica, but no specimens have
been seen by naturalists. The largest Cuban Cave-Fish is 5 inches
long.[755]
FAM. 13. CONGROGADIDAE.—Eel-shaped Fishes without ventrals, allied to the
Blenniidae, but with all the rays soft and articulated, the post-temporal
small and ankylosed to the skull, and the sub-orbitals produced into
laminae supporting the eyeball. Lips much developed; gill-membranes free
from isthmus; scales very small.
A single genus, _Congrogadus_, with three species from the Australian and
East Indian coasts. The recently described Japanese genus _Hierichthys_ has
been referred to this family.
FAM. 14. OPHIDIIDAE.—Degraded Blenniids, closely related to the Zoarcidae,
with pseudobranchiae, with tapering tail without distinct caudal fin, and
with the ventral fins each reduced to a pair of filaments or a bifid ray
inserted just behind the chin at the extremity of the clavicle, which is
produced forwards as a slender rod.
Small marine, carnivorous fishes, from the Atlantic and Southern Pacific
coasts as well as from great depths in the Atlantic, Pacific, and Indian
Oceans. About 25 species are known. Genera: _Ophidium_, _Lepophidium_,
_Genypterus_.
FAM. 15. PODATELIDAE.—Mouth inferior, protractile, toothless or with minute
teeth. Praecaudal vertebrae with transverse processes, to which the ribs
are attached. Gill-membranes narrowly attached to isthmus; 8 or 9
branchiostegal rays; gills 4; no pseudobranchiae. Supratemporal loosely
attached by ligament to the skull; scapula cartilaginous, perforate,
bearing the base of the pectoral fin, which is an undivided cartilaginous
plate; coracoid small, ossified. Ventral fins jugular, each reduced to a
single stout filament made up of two intimately coherent rays. Body short,
tail elongate and tapering, {714}compressed; no scales. A short dorsal fin,
without spines, situated above the pectorals; a long anal fin, continuous
with the caudal.
[Illustration: FIG. 431.—Pectoral arch of _Podateles indicus_. _cl_,
Clavicle; _cor_, coracoid; _pelv_, pelvis; _ptr_, pterygial; _ptte_,
post-temporal; _sc_, scapula; _scl_, supraclavicle.]
The genus _Podateles_ (_Ateleopus_) comprises only two species from the
deep sea, one from Japan and one from India.
DIVISION IX.—TAENIOSOMI.
Exceedingly compressed, more or less elongate, often ribbon-like fishes of
doubtful affinities, probably related to the earlier Acanthopterygians, the
ventral fins, when well developed, comprising as many as 7 to 9 rays.
Dorsal fin extending from the head to the end of the tail, its rays simple
(separable into lateral halves), the anterior often prolonged; anal fin
very short or absent. Pectoral fin with horizontal or nearly horizontal
base, the rays supported by the scapula and by three short pterygials, all
three, or two at least, of which are related to the coracoid. Ribs small
and slender, or absent. Post-temporal simple and solidly attached to the
skull. Scales minute or absent.
Deep-sea or pelagic fishes from the Atlantic and Mediterranean and from the
Pacific; the life-histories are still very imperfectly known, and great
changes of form take place with growth. Only two families.[756]
{715}FAM. 1. TRACHYPTERIDAE.—Mouth very protractile; ventral fins more or
less developed, with 6 to 9 rays, or reduced to a single long ray; no anal
fin; vent about the middle of the body; caudal rays, if present, divided
into two fascicles, the upper sometimes much prolonged and directed
upwards.
[Illustration: FIG. 432.—_Trachypterus iris_. × 1. (After Cuvier and
Valenciennes.)]
Two genera. The most generalised is _Trachypterus_, of which probably only
10 forms are entitled to specific distinction. The best known species is
_T. arcticus_, the Deal-Fish or Northern Ribbon-Fish, which reaches a
length of 8 feet or more, and of which a few specimens have been stranded
on the coasts of Scotland. Nilsson, who has observed these fishes alive on
the Scandinavian coast, says they approach the shore at flood-tide on sandy
shelving bottoms, and are often left by the retreating waves; that they
move with one side turned obliquely upward, and that they lie on the side
like Flat-Fishes on the bottom in 2 or 3 fathoms of water. _Regalecus_
differs in the presence of a single ray to the ventral and the absence of
the caudal fin. Some 5 or 6 species may be distinguished. _R. glesne_, the
Oar-fish, or "King of the Herrings," is the best known and the largest
species, reaching a length of over 20 feet. About 25 {716}specimens are
known to have occurred on the British coasts. Some of the accounts of
"Sea-Serpents" are probably based on this fish, which has been observed to
swim with undulating motion and with a small portion of the head as well as
the crest-like anterior part of the dorsal fin above the water.
The fish named _Stylophorus chordatus_, which has been referred to this
family, is known from a single specimen too imperfectly preserved to afford
a clear idea of its affinities.
FAM. 2. LOPHOTIDAE.—Mouth moderately protractile; ventrals very small, if
distinct, with 4 or 5 rays; abdominal cavity extending nearly the whole
length of the much elongated body, the vent very far back and followed by a
short anal fin; caudal fin small, not divided.
A single genus, _Lophotes_, with 3 or 4 species, from the Mediterranean,
the tropical Atlantic, the Cape of Good Hope, Japan, and New Zealand,
reaching a length of 6 feet or more. The dorsal fin commences with an
extremely long and strong spine on the head, which is much elevated and
truncate in front.
SUB-ORDER 11. OPISTHOMI
Air-bladder without open duct. Opercle well developed, hidden under the
skin; supraoccipital in contact with the frontals, separating the
parietals. Pectoral arch suspended from the vertebral column, far behind
the skull; no mesocoracoid. Vertical fins with spines. Ventral fins absent.
This division stands in the same relation to the Acanthopterygii as do the
Apodes to the Malacopterygii. The single family is possibly derived from
the Blenniidae.
FAM. 1. MASTACEMBELIDAE.—Body more or less Eel-shaped; a series of short
spines detached from the very elongate dorsal fin, which is more or less
confluent with the likewise very elongate anal fin. A single nostril on
each side. Mouth not protractile, bordered by the praemaxillaries, to the
upper border of which the maxillaries are attached. Gill-cleft inferior;
gills 4; branchiostegal rays 6; no pseudobranchiae. Vertebrae numerous
(72-95), the praecaudals with transverse processes bearing the ribs. Scales
very small.
Carnivorous fishes, from fresh and brackish waters of Southern Asia and
Tropical Africa. 33 species are known, referable to {717}two genera:
_Mastacembelus_ and _Rhynchobdella_. The largest species reach a length of
three feet. Little is known of their habits. Of the Indian _Rhynchobdella
aculeata_, Day says it conceals itself in the mud and becomes drowned in
water if unable to reach the surface, as it apparently requires to respire
air directly.
[Illustration: FIG. 433.—_Mastacembelus maculatus_. × ½.]
SUB-ORDER 12. PEDICULATI.
Air-bladder without open duct. Opercle large, hidden under the skin;
supraoccipital in contact with the frontals, separating the parietals.
Pectoral arch suspended from the skull; no mesocoracoid. No ribs, no
epipleurals. Ventral fins jugular. Gill-opening reduced to a foramen
situated in or near the axil, more or less posterior to the base of the
pectoral. Body naked or covered with spines or bony tubercles.
A small, natural group, connected with the Acanthopterygii Jugulares
through the Batrachidae, in which the elongate pterygials of the pectoral
fin foreshadow the kind of arm ("pseudobrachium") which is more or less
characteristic of these highly aberrant Fishes. As in the Batrachidae, the
post-temporal is flat and ankylosed to the cranium, and the suprascapula is
much elongated. The pterygials, two or three in number, are separated from
the small scapula and coracoid by a broad ligament, the arm-like pectorals
being more or less distinctly geniculated and inserted far back behind the
cranium. The head is large, the basis cranii simple. The gills are reduced
to 2, 2½, or 3. The spinous dorsal, if present, consists of a few rays,
which may be modified into tentacles inserted on the head. Vertebrae 17 to
31.
{718}Five families:—
I. Gill-opening in or behind lower axil of pectoral; mouth large,
terminal or directed upwards.
Pectoral fin scarcely geniculated; ventrals present 1. _Lophiidae_.
Pectoral fin scarcely geniculated; ventrals absent 2. _Ceratiidae_.
Pectoral fin strongly geniculated; ventrals present 3. _Antennariidae_.
II. Gill-opening behind lower axil of pectoral; mouth large, inferior;
ventrals absent 4. _Gigantactinidae_.
III. Gill-opening above axil of pectoral; mouth rather small,
subterminal or inferior; pectoral fin strongly geniculated; ventrals
present; spinous dorsal absent or reduced to a small tentacle lodged
in a cavity under the snout 5. _Malthidae_.
FAM. 1. LOPHIIDAE.—Mouth extremely large, terminal, with very strong
cardiform teeth. Gill-opening in lower axil of pectoral; pseudobranchiae
present. Pectoral fin scarcely geniculated, with two pterygials. Ventral
fin with 1 spine and 5 branched rays. Spinous dorsal present. Skin naked.
Twelve species, referable to three genera (_Lophius_, _Chirolophius_, and
_Lophiomus_) living on the bottom of the Atlantic, Indian, and Pacific
Oceans, at moderate or great depths. _Lophius_ was represented in the Upper
Eocene of Monte Bolca.
[Illustration: FIG. 434.—_Chirolophius naresii_. (After Günther.) × ⅓.]
The Fishing-Frog or Angler (_Lophius piscatorius_) has a wide distribution,
occurring on the coasts of Europe and North America. The first dorsal ray,
inserted on the snout, is very long, movable in every direction, and
terminates in a dermal flap, which is supposed to be used by the "Angler"
as a bait, attracting other fishes, which are soon ingulfed in the enormous
gape. It grows to a length of over 5 feet. The ventral rays are very
elongate in the young.
{719}FAM. 2. CERATIIDAE.—Mouth extremely large, terminal, with strong
cardiform teeth. Gill-opening in lower axil of pectoral; pseudobranchiae
absent. Pectoral fin scarcely geniculated, with three pterygials. Ventral
fins absent. Spinous dorsal fin usually present, sometimes reduced to a
single tentacle on the snout. Skin naked.
The members of this family, about 25 in number, are all inhabitants of
great depths (300-2600 fathoms). The colour of the body is usually a deep
black, and the first dorsal spine, on the head, may terminate in a luminous
bulb with or without filaments. "The Bathybial Sea-devils," writes Günther,
"are degraded forms of _Lophius_; they descend to the greatest depths of
the ocean. Their bones are of an extremely light and thin texture, and
frequently other parts of their organisation, their integuments, muscles,
and intestines are equally loose in texture when the specimens are brought
to the surface. In their habits they probably do not differ in any degree
from their surface representative, _Lophius_."
[Illustration: FIG. 435.—_Himantolophus reinhardti_, outline and skeleton.
(After Lütken.) × 1.]
Principal genera: _Ceratias_, _Aceratias_, _Oneirodes_, _Himantolophus_,
_Aegaeonichthys_, _Melanocetus_, _Liocetus_, _Linophryne_, _Caulophryne_,
_Dolopichthys_.
{720}FAM. 3. ANTENNARIIDAE.—Mouth large, vertical or very oblique, turned
upwards, with cardiform teeth. Gill-opening in or behind lower axil of
pectoral; pseudobranchiae absent. Pectoral fin forming an elbow-like angle,
with three pterygials. Ventral with 4 or 5 rays. Spinous dorsal present.
Skin naked or spinulose.
About 40 species, referable to 5 genera: _Pterophryne_, _Antennarius_,
_Brachionichthys_, _Saccarius_, and _Chaunax_.
The species of _Antennarius_ live mostly in coral groves, where they lie in
wait for prey, well concealed by their protective coloration and the
harmonising aspect of their integument and appendages. To this genus also
belongs the "Marbled Angler" (_A. marmoratus_), carried about in mid ocean
among the _Sargassum_ weed, to rest on which, from its peculiar arm-like
pectoral fins, it is specially fitted; there it makes its wonderful nest of
silk-like fibres, probably secreted by the parent as in the Sticklebacks,
with large bundles of eggs hanging like grape clusters.[757] The deep-sea
_Chaunax_ inflates its abdomen like _Tetrodon_.
FAM. 4. GIGANTACTINIDAE.—Mouth inferior, snout produced into a long
tentacle directed forwards, and bearing a luminous organ. Body covered with
small spines. Otherwise as in the Ceratiidae. _Gigantactis vanhoeffeni_, of
Brauer, from the Indian Ocean, at depths of about 1000 fathoms.
FAM. 5. MALTHIDAE.—Mouth rather small, subterminal or inferior, with
villiform or cardiform teeth. Gill-opening above pectoral; pseudobranchiae
absent. Pectoral fin forming an elbow-like angle, with three pterygials.
Ventral with 5 rays. Spinous dorsal absent, or reduced to a more or less
developed tentacle lodged in a cavity under the snout. Head and body with
bony tubercles or spines.
About 30 species are known, mostly from the deep sea within the tropics
(down to 1270 fathoms). Principal genera: _Coelophrys_, _Malthe_,
_Malthopsis_, _Halieutaea_, _Halicmethes_, _Dibranchus_.
The "Bat-Fish" (_Malthe vespertilio_), common in shallow water about the
West Indies, is said to assume an almost toad-like attitude on the ground,
the head being directed slightly upwards, while the pectorals take on the
function of hind legs and the ventrals of fore legs.
{721}SUB-ORDER 13. PLECTOGNATHI.
Air-bladder without open duct. Opercular bones more or less reduced;
supraoccipital in contact with the frontals, separating the parietals;
maxillary and praemaxillary bones often firmly united. Pectoral arch
suspended from the skull. No ribs. Ventral fins thoracic and much reduced
if present; the pelvic bones, if present, more or less completely
co-ossified. Gill-opening much reduced. Body covered with more or less
osseous scales, bony scutes, or spines, or naked.
A highly aberrant group, closely connected with the Acanthopterygii through
the Acanthuridae, as pointed out long ago by Dareste.[758] The skeleton is
often feebly ossified and the vertebrae much reduced in number, but the
jaws, although short, are very strong, usually with large sectorial teeth
which may be confluent into a beak; the post-temporal is short and simple,
suturally united to the squamosal. These fishes have usually been arranged
in three divisions: _Sclerodermi_, _Ostracodermi_, and _Gymnodontes_, but
Regan,[759] whose classification is here followed, has shown that the
latter include a type (_Triodon_) which, in spite of its beak-like teeth,
is more nearly related to the Sclerodermi, whilst the Ostracodermi have
much more in common with the latter than with the Gymnodontes. It therefore
appears best to admit only two divisions, the first with 4, the second with
3 families:—
I. SCLERODERMI.—Supraclavicle vertical; pectoral arch of the
Perciform type; all the vertebrae with a single neural spine.
A. Body covered with hard or spinous scales; epipleurals present;
pelvis present.
Teeth separate; spinous dorsal present; ventrals paired; pelvis
immovable 1. _Triacanthidae_.
A beak; spinous dorsal and ventrals absent; pelvis movable
2. _Triodontidae_.
Teeth separate; spinous dorsal present; ventrals absent or
represented by a single short spine; pelvis movable
3. _Balistidae_.
B. Body encased in a carapace; no epipleurals; spinous dorsal,
pelvis, and ventrals absent 4. _Ostraciontidae_.
II. GYMNODONTES.—Supraclavicle oblique or nearly horizontal; lower{722}
three pterygials enlarged and immovably united to the coraco-scapular
cartilage; anterior vertebrae with bifid divergent neural spines;
pelvis absent.
Beak with a median suture; interoperculum not connected with
suboperculum; caudal fin present; body inflatable.
1. _Tetrodontidae_.
Beak without median suture; interoperculum attached posteriorly to
suboperculum; caudal fin present; body inflatable.
2. _Diodontidae_.
Beak without median suture; interoperculum attached posteriorly to
suboperculum; caudal fin absent, the body non-inflatable,
truncate posteriorly, with the dorsal and anal fins confluent.
3. _Molidae_.
[Illustration: FIG. 436.—Left side of pectoral arch of A, _Triacanthus
brevirostris_, and B, _Tetrodon mbu_. _cl_, Clavicle; _cor_, coracoid;
_pcl_, post-clavicle; _p.r_, pectoral rays; _ptr_, pterygials; _sc_,
scapula; _scl_, supraclavicle.]
DIVISION I.—SCLERODERMI.
Supraclavicle vertical; pectoral pterygials not enlarged, movably attached
by ligament to the scapula and coracoid, three to the former and one to the
latter. All the vertebrae with the neural arches forming a single spine.
Basis cranii more or less distinctly double; dentary and articular
completely co-ossified.
FAM. 1. TRIACANTHIDAE.—Praemaxillaries protractile, free from the
maxillaries; teeth in the jaws separate, conical or incisor-like; palatine
arch firmly united to the skull. Gills 4. Praecaudal vertebrae with
parapophyses; epipleurals present. Spinous dorsal fin with 2 to 6 spines.
Ventral fins each represented by a strong spine, with an inner basal knob
which locks it when everted, rarely with the addition of 1 or 2 rudimentary
soft rays; pelvis present, firmly united to the pectoral arch. Scales
small, sometimes spinous or bony. Vertebrae 20.
Marine fishes from the Indian and Western Pacific Oceans. Ten species,
referable to three genera: _Triacanthus_, _Triacanthodes_,
{723}_Halimochirurgus_. The latter, remarkable for its long, tube-like
snout, is the only deep-sea form of this Sub-order; it was recently
discovered in the Gulf of Manaar, at a depth of 143 fathoms. Fossil genera
are _Acanthopleurus_, Oligocene, and _Spinacanthus_, Eocene.
FAM. 2. TRIODONTIDAE.—Praemaxillaries not protractile, firmly united to the
maxillaries; teeth coalescent into a beak, the upper jaw divided by a
median suture, the lower simple. Praecaudal vertebrae with or without
parapophyses; epipleurals present. No spinous dorsal fin. No ventral fins.
Abdomen with a dilatable sac, kept expanded by the very long movable
pelvis. Body covered with small, spiny, subimbricate, bony laminae.
Vertebrae 20.
A single species, the curious _Triodon bursarius_ of the Indian Ocean and
Archipelago.
[Illustration: FIG. 437.—_Monacanthus_, sp., with enlarged views of dorsal
scales (_b_) and ventral spine (_c_).]
FAM. 3. BALISTIDAE.—Praemaxillaries not protractile, firmly united to the
praemaxillaries; teeth incisor-like; palatine movably articulated with
ectopterygoid, or entirely free from it. Gills 4. Praecaudal vertebrae with
well-developed parapophyses, to which epipleurals are attached. Spinous
dorsal fin with 1 to 3 spines. Ventral fins, if present, represented by a
single short {724}rough spine at the end of the long, movable pelvis. Body
covered with juxtaposed movable scutes or with minute rough scales.
About 100 species are known from the tropical and warm seas, one species
(_Balistes capriscus_) occasionally wandering as far north as the south
coast of England. Genera: _Balistes_, _Monacanthus_, _Paraluteres_,
_Pseudaluteres_, _Pseudomonacanthus_, _Aluteres_, _Psilocephalus_. The
Oligocene genus _Acanthoderma_ is closely allied to _Balistes_.
The "File-Fishes" or "Trigger-Fishes" (_Balistes_), the largest species of
which grow to nearly 3 feet, have a powerful dentition, which enables them
to break off pieces of corals, on which they feed, and to bore holes in the
hard shells of Mollusca in order to extract the soft parts; they are
themselves well protected by a mail of hard, rhomboidal scales. The
herbivorous _Monacanthus_ is less favoured in this respect, the rough
scales being so small as to give the skin a velvety appearance.
_Psilocephalus_ differs from _Monacanthus_ in its very elongate head and
body, the very feeble dorsal spine, the presence of a mental barbel, and
its more numerous vertebrae (29 or 30 instead of 18 to 21). The flesh of
many of these fishes is poisonous.[760] The drumming sounds produced by
_Balistes_ have been described by Möbius.[761]
FAM. 4. OSTRACIONTIDAE.—Praemaxillaries not protractile, firmly united to
the praemaxillaries; teeth incisor-like; palatine immovable. Gills 4.
Praecaudal vertebrae with very feeble parapophyses and no epipleurals. No
spinous dorsal fin. Clavicles, coracoids, and post-clavicles much expanded.
No ventral fins. Body encased in a carapace formed of large, juxtaposed,
mostly hexagonal bony plates. Vertebrae 14 to 16.
The species of "Trunk-Fishes" number about 20, and are referable to 3
genera: _Aracana_, _Ostracion_, _Lactophrys_; all belong to the tropical
seas, living near the bottom in shallow water. The genus _Ostracion_ is
represented by one species in the Upper Eocene.
The rigid box in which these fishes are encased entails more use of the
dorsal and anal fins for progression than is customary {725}among fishes.
According to Brown Goode, "the propelling force is exerted by the dorsal
and anal fins, which have a half rotary, sculling motion, resembling that
of a screw propeller; the caudal fin acts as a rudder, save when it is
needed for unusually rapid swimming, when it is used as in other fishes;
the chief function of the broad pectorals seems to be that of forming a
current of water through the gills, thus aiding respiration, which would
otherwise be difficult on account of the narrowness and inflexibility of
the branchial apertures. When taken from the water, one of these fishes
will live for two or three hours, all the time solemnly fanning its gills,
and when restored to its native element seems none the worse for its
experience, except that, on account of the air absorbed, it cannot at once
sink to the bottom." "No group of tropical fishes," says the same author,
"is so thoroughly worked out in the writings of the fathers of natural
history as this one. Over 200 years ago every species of trunk-fish now
taken from the Atlantic was known to and described by the naturalists, and
it is a well-deserved tribute to their discrimination as zoologists to say
that none of the many efforts which have since been made to subdivide their
species have been at all successful."
[Illustration: FIG. 438.—_Ostracion quadricornis_. × ½.]
DIVISION II.—GYMNODONTES.
Supraclavicle oblique, sometimes nearly horizontal; lower three pectoral
pterygials enlarged and immovably united to the coracoscapular cartilage;
upper pterygial small, suturally united to the scapula. Anterior vertebrae
with bifid divergent neural spines. Basis cranii simple; suture between
dentary and articular evident. Pelvis absent.
The spinous dorsal and the ventral fins are constantly absent, the
praemaxillaries are united to the maxillaries, and the teeth {726}are
coalescent, forming a beak; parapophyses are not developed, and epipleurals
are absent.
FAM. 1. TETRODONTIDAE.—Beak with a median suture. Interoperculum a long
rod, attached to inner face of praeoperculum, sometimes connected with
operculum, never with suboperculum. Gills 3. First 4 or 5 praecaudal
vertebrae with bifid neural spine and closed neural arch. Skin naked or
with movable spines, rarely with bony plates; belly inflatable. Vertebrae
17 to 29.
The "Puffers" or "Globe-Fishes" comprise about 60 species, referable to 5
genera: _Tetrodon_, _Ephippion_, _Tropidichthys_, _Xenopterus_,
_Chonerhinus_. They inhabit all the tropical and warm seas, a few species
being confined to fresh water. Remains of _Tetrodon_ have been found in
Upper Eocene and later formations. They are remarkable for the manner in
which they inflate themselves with air.[762] The flesh of most species is
poisonous.
FAM. 2. DIODONTIDAE.—Beak without median suture. Interoperculum rod-like,
attached posteriorly to the rod-like anterior limb of the suboperculum.
Gills 3. All the praecaudal vertebrae with bifid neural spines. Skin with
movable spines; belly inflatable. Vertebrae 21 or 22.
[Illustration: FIG. 439.—_Diodon geometricus_. (After Goode.)]
Only two genera appear capable of clear definition: _Diodon_ and
_Lyosphaera_; species about 15. Numerous species have been described from
the Upper Eocene and later formations.
"Porcupine Fishes" are confined to tropical seas, and have attracted
attention from the earliest times, being frequently preserved as
"curiosities." Their flesh is regarded as poisonous.
FAM. 3. MOLIDAE.—Beak without median suture. Interoperculum rod-like,
attached posteriorly to the rod-like anterior limb of the suboperculum.
Gills 4. Anterior praecaudal vertebrae with divergent bifid neural spines
and neural canal not roofed in. {727}Body non-inflatable, truncate
posteriorly, without caudal peduncle; caudal fin absent, the dorsal and
anal fins confluent. Skin rough or tessellated. Vertebrae 17 in
_Orthagoriscus_.
The very young are armed with spines.
[Illustration: FIG. 440.—_Orthagoriscus mola_. (After Goode.) × 1/20.]
The "Sun-Fish" are extraordinary creatures found in the open sea or
descending to great depths, and of wide distribution. The number of species
is still very uncertain, but two generic forms, _Orthagoriscus_ or _Mola_
and _Ranzania_, are easily distinguished. Examples of both occur now and
then on our coasts. _Orthagoriscus mola_ grows to upwards of 8 feet and to
a weight of 1800 pounds. It has been observed to swim slowly about, near
the surface, the high dorsal above the water. Its food is said to consist
chiefly of jelly-fish and larval fishes; its mode of reproduction and
places of breeding are still unknown.
{729}INDEX
Every reference is to the page: words in italics are names of genera or
species; figures in italics indicate that the reference relates to
systematic position; figures in thick type refer to an illustration; f. =
and in following page or pages; n. = note.