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ire composed of a very few soft rays. In the anal fin, the spines are few or
wanting, and there is very generally a papilla in the neighbourhood of the vent.
Hie low and elongate body is more or less cylindrical in form, and either naked or
covered with scales, which are generally of small size. The dorsal fin, which may
either single, double, or triple, occupies nearly the whole length of the back ;
ind when it has a distinct spinous portion, this is at least as much developed as the
>oft part, while in some instances the whole fin may be spiny , the anal being




JAPANESE CHIRUS.



igate. In most cases false gills are present. All the marine members of the
lily are littoral forms, and the majority are of small size, while some are among
smallest of all fishes. They are abundant throughout all tropical and temperate
seas ; and whereas some forms inhabit brackish water, others are exclusively fresh-
vater. Dr. Giiiithcr writes that " one of the principal characteristics of the
Pennies is the ventral [pelvic] fin, which is formed by less than five rays, and has
jugular position. The blennies have this in common with many gadoids [cod
iribe], and it is sometimes difficult to decide to which of these two families a fish
should be referred. In such doubtful cases the presence of the pseudobranchiae
which are absent in gadoids) may be of assistance. In many blennies the ventral
ins have ceased to have any function, and become rudimentary, or even entirely
ibsent. In others, the ventral fins, although reduced to cylindrical stylets, possess
i distinct function, and are used as organs of locomotion, by the aid of which the
ash moves over the bottom." The family is not definitely known in a fossil state,
ilthough it may be represented by an extinct genus in the Monte Bolca Eocene.



394 SPINY-PINNED GROUP.

The blennies of the typical genus Blennius, of which there are some forty
species, are found in the northern seas, the Tropical Atlantic, the coasts of Tasmania,
and the Red Sea. They are characterised by the moderate elongation of the naked
body, the short snout, the single continuous dorsal fin, and the presence of one
spine and two rays in the pelvics. The cleft of the mouth is narrow, the jaws
contain a single series of fixed teeth, behind which there is generally one larger
curved tooth, at least in the lower jaw. Above each eye is the longer or shorter
tentacle, and the gill-opening is relatively wide. Among British species we have
the eyed blenny (B. ocellatus), distinguished by the dark spot on the elevated
spinous portion of the dorsal, the smooth blenny or shanny B. pkolis, and the large
B. gattorugine, which may grow to a foot in length ; while as an example of
a species living in inland lakes we may cite the fresh-water blenny (B. vulgaris) <>i
Southern Europe. Most can be readily accustomed to a fresh-water life, and many
of the marine species attach themselves to floating objects, while some are found
far out at sea among the patches of drifted seaweed. In the Indian seas the
blennies are represented by seven more or less closely allied genera, in one of which
(XipJiasia) the body is band-like, and the caudal fin continuous with the dorsal
and anal.

viviparous The fish (Zoarces viviparus) of which two examples are repre-

Biennies. sented in the lower part of the illustration on p. 387, is one of two
species of a genus remarkable for producing living young. With an elongate body,
rudirnental scales, and conical teeth in the jaws, these fish have an extremely
elongated dorsal fin, separated from the caudal merely by a depression formed by
a series of spines much shorter than the rays; these spines being the only om^
throughout the fins. The pelvic fins are composed of three or four rays ; and the
long anal fin is continuous posteriorly with the caudal. The gill-openings are wide.
While the figured European species, which is not uncommon on the British coasts,
does not exceed a foot in length, its Transatlantic cousin (Z. anguillaris) may
measure two or three times as much. The fry, which at birth are perfeci 1 y
transparent, and form beautiful objects for the microscope, are so fully developed
as to be able at once to swim freely on leaving the body of the female parent.
Before their birth the female becomes so distended, that at the slightest pressi
the young are extruded; these frequently being from two to three hundred
number, and always making their appearance in the world head first. The genei
colour of the adult fish is pale brown, with the dorsal fin and upper-parts mottle
and barred with darker brown.

Easily recognised by the powerful tuberculated and molar-lil
teeth with which their mouths are armed, the wolf-fishes (Anarrl
ckas) may be regarded merely as gigantic and somewhat specialised blennies.
this genus, which is represented by a small number of species from the northe:
seas of botli the Eastern and Western Hemispheres, the elongate body is cove
with rudimental scales ; the muzzle is rather short and the cleft of the mouth wi
and the jaws are armed with strong conical teeth, those of the lateral series carry-
ing several pointed cusps, while a double row of large molar-like teeth runs dow
the middle of the palate. The long dorsal fin lias flexible spines, and there is
distinct caudal, but the pelvic pair are quite wanting. The gill-opening is wide.






SPINY EELS.



395



The common wolf-fish (A. lupus), often known as the sea-wolf or sea-cat, like two
allied species, ranges as far north as Norway and Greenland ; in both of which
countries its flesh forms a staple article of food.

owique-Spined The fifth family (AcantJtoclinidce) of the section under con-
Eienny. sideration is represented only by the New Zealand oblique-spined
blenny (Acanthoclinus littoreus), shown in the annexed illustration, and is charac-
terised by the elongate, low, compressed, and scaly body, the single dorsal fin
chiefly composed of spines occupying nearly the whole length of the back, and
the comparatively long and many-spined anal ; the pelvic fins being jugular
in position, and consisting solely of a few soft rays. On the coasts of New
Zealand this blenny is stated to be a very common fish ; its habits being probably
similar to those of its European cousins.




Spiny Eels.



OBUQUE-Sl'INED BLENNY (liat. size).

The so-called spiny eels of the Oriental region and West Africa
form a family (Rkynckobdellidcv) affording an interesting example
of parallelism in development, since these spiny-finned eels are an exact analogue
of the true soft-filmed eels. They are characterised by the elongate eel-like
form of the body ; the long dorsal fin, of which the anterior portion consists of
short isolated spines , and the absence both of pelvic fins and of a papilla in the
neighbourhood of the vent. The gill-opening forms a slit on the side of the head ;
four gills are contained in the gill-chamber, and there are no false gills. An
'longated movable appendage forms the termination of the muzzle, and although
the lower jaw is long, it has but little power of motion. As an especial peculiarity
>f these fishes, we may notice that in the skeleton there is no connection between
the pectoral girdle and the skull. The air-bladder is present. The species
Mastacembelus HI'IIKI/HN), shown in the upper figure of the illustration on p. 8!)(5,
s one of the Indian representatives of a genus characterised by the smooth
.inder surface of the appendage of the snout, and the presence of a preorbital
^pine. The members of this genus have a geographical distribution, coextensive
with that of the family, being found in the brackish and fresh waters of West
Airica, India, Ceylon, Burma, and the Malayan region. On the other hand,



39 6



SPINY-PINNED GROUP.



the genus RhynckobcMla, characterised by the striation of the lower surface of the
nasal appendage, and the lack of a spine in front of the eye, is confined to India
and Burma, where it is represented by R. aculeata, which grows to a length of
about 15 inches, and is found in the deltas of all the larger rivers, generally
preferring muddy pools. The figured species is, however, of larger size, reaching
a couple of feet in length. The flesh of all the spiny eels is stated to be of
excellent quality for the table.

The fish represented in the lower portion of the annexed illus-
tration, known as the Baikal oil-fish (Coinephorus baikalensis), is
the only representative of a genus in regard to the systematic position of
which there is considerable doubt ; Dr. Giinther regarding it as indicating a
distinct family which he at one time placed in the neighbourhood of the oblique-



Oil-Fish.



INDIAN SPINY EEL (\ nat. size).



BAIKAL OIL-FISH (^ nat. size).




spined blenny, and afterwards near the flying gurnards. In this fish the
is elongate and naked, the head large with a produced muzzle, medium-s
lateral eyes, and small teeth. There are two dorsal fins, of which the first
much shorter than the second, which is similar to the anal; the pelvic tins
wanting, and there is no papilla near the vent. The gill-opening is wide ; the
are four gills, and no air-bladder. The skeleton is very soft ; and the elemei
of the gill-cover are not distinctly differentiated. In colour this strange fish
uniformly greenish, and its pectoral fins are remarkable for their large si/
While the oil-fish presents some resemblance to the dragonets, it differs by
compressed body, the large, broad-snouted head, the elongation of many
the rays of the second dorsal fin, the large pectorals, the absence of pelvic fii
and the forked tail. So far as present information goes, the oil-fish is confined'
to Lake Baikal, where in winter it retires to the greatest depths, but approaches



BARRACUDAS AND SAND-SMELTS. 397

j!the shore in the warmer months. Swimming with remarkable speed, it is enabled
by the length of its pectorals to take considerable leaps above the surface of the
.water, and thus approaches the flying-fish. During stormy weather great numbers
jof these fishes are frequently stranded, when they are collected by the nati\ 7 es for
[the purpose of extracting the oil from them.

BARRACUDAS, ATHERINES, AND GREY MULLETS, Families

A THERINID^:, and



Following Dr. Glinther's classification, these three families form a sectional
group differing from those we have been considering by the position of the pelvic
fins, which are abdominal, and have one spine and five soft rays. The two dorsal
fins are situated more or less remote from one another, the first being either short,
like the second, or composed of weak spines.

The large and ferocious fishes commonly known as barracudas

(Sphyrcena), of which a species (8. vulgaris) is shown in the upper

ifigure of the illustration on p. 379, are the sole existing representatives of the

first family, which is distinguished by the elongated and subcylindrical form

| of the body, the large cutting-teeth, the continuous lateral line, and the presence

; of only twenty-four vertebrae in the backbone. The scales are small and cycloidal ;

the cleft of the mouth is wide; and the medium-sized eyes have a lateral position.

Represented by something less than a score of species, barracudas are distributed

over all temperate and tropical seas, but generally prefer the neighbourhood of

the coast to the open ocean. They are all carnivorous and fierce in their dis-

j position, and since they frequently grow to 6 or 8 feet in length, they are as

much or even more dreaded by bathers in seas where they are common than

sharks. They are extensively caught for food, but in some instances, from their

having fed on poisonous kinds of fish, their own flesh becomes impregnated with

the venom. Moseley writes that " there is a great fishery at the Cape, of a fish

called snook, a kind of barracuda, which is salted and dried, and sent mainly to

Mauritius for sale. The snook -boats were always to be seen about in the bay.

The fish are caught with a hook and line whilst the boat is in motion. The

fishermen are especially careful not to get bitten by the fish as they haul them in,

wounds caused by their bite being said to fester in a violent manner, as if

inflamed." Fossil barracudas occur in the middle Eocene of Monte Bolca ; while

in the Cretaceous rocks of the Lebanon and Brazil the family is represented by

the extinct genus Cladocyclus.

The second family of the group under consideration is typically
represented by the so-called sand-smelts; one of the two British
species (Atherina hepsetus) being shown in the left figure of our illustration.
As a family, the Atherinidce are distinguished from the barracudas by the
indistinct lateral line ; the feeble or moderately developed dentition ; and by
the number of vertebra? being usually in excess of twenty-four. The body is
more or less elongate, with but slight compression. In the sand-smelts the scales
are smooth and cycloid, and the teeth minute ; the first dorsal fin is short and
completely separate from the second ; and the muzzle is blunt, with the cleft



398



SPINY-FINNED GROUP.



of the mouth straight, oblique, and extending at least as far back as the line of
the border of the eye. These fish derive their popular title from their resemblance
to the true smelts, from which they may be distinguished at a glance by the
small spinous first dorsal fin. While the majority are coast fishes, associating in
large shoals, others are fresh-water, although these also retain the same habit.
The genus has a wide distribution in temperate and tropical seas, some of the
species ranging from Eastern Africa to India. Atherines are very abundant iu
the Mediterranean, where the fry cling together for some time after hatching
enormous masses. Montagu writes that these fish are caught in great



111



abundance on the south coast of Devonshire "in the creeks and estuaries, but




SAND-SMELT AND CUVIKK'



never in rivers above the flow of the tide ; and they appear to continue near
shore through the months from autumn to spring, being caught for the table
more or less during the whole of that time, but are greatly superior in spring.
when the males are full of milt as the females are of roe." The British species
seldom exceed 6 inches in length, and, like the other members of the genus, are
marked by a broad silvery stripe along each side of the body. On the coasts and
in the fresh waters of Australia, the sand-smelts are represented by A/hcr/n-
icktkys, in which the muzzle is longer, and the cleft of the mouth usually shorter.
The curious Mediterranean and Atlantic fish known as Cuvier's
square-tail (Tebragonwrua cuvieri), shown on the right side of our
illustration, is the sole member of a genus characterised by the somewhat elongate



Square-Tail



GRE Y MULLETS.



399



body being covered with strongly keeled and striated scales; and by the first
lorsal fin being composed of a number of short spines, and continuing to the
second. The elevated lower jaw has a convex upper border, bearing a single
series of rather small compressed and triangular teeth. Of the habits of this
scarce fish nothing definite seems to be known ; although in the young state it
s found in company with floating jelly-fish. At a later period of its existence
t probably descends to a considerable depth during the day, and comes to the
surface only at night. It grows to a foot and a half in length.

From the two preceding families the grey mullets, which con-
stitute the third family of the group under consideration, may be
tistinguished by the total absence of a lateral line, the presence of only four stiff
spines in the first dorsal fin, and the limitation of the number of vertebrae in the
skeleton to twenty-four. The more or less elongate and somewhat compressed
is covered with cycloid or slightly ctenoid scales of moderate size ; the cleft



Grey Mullets.



COMMON GREY MULLET (J nat. size).




the mouth is small or medium ; the teeth are feeble or wanting ; the lateral eye
of moderate size ; and the gill-opening wide. In some species there may be
fatty lid to the eye. The grey mullets (Miujil), of which there is a very large
lumber of species, are distributed over all temperate and tropical coast-regions,
frequenting brackish-water estuaries, and in some cases ascending rivers for
onsiderable distances. Feeding chiefly upon the animals and organic matter
found in sand and mud, these fishes have a special straining apparatus in the
)harynx for the purpose of preventing objects of too large size from entering
the stomach, or foreign substances getting into the gill-chamber, It will be
mecessary to describe the structure of this apparatus here ; but it may be
lentioned that after triturating a mouthful of sand or inud between the
Jpharyngeal bones, in order to extract such nutriment as it may contain, the grey
[mullets reject the mineral part of it. Another peculiarity is to be found in the
structure of the oasophagus and stomach, the former being lined with long thread-
like papillae, while the latter has its second portion furnished with muscular walls
like the gizzard of a bird, although it is not divided into two lateral halves,



400 SPINY-FINNED GROUP.

A fossil species of grey mullet has been described from the upper Eocene of
Provence, and an extinct genus from the Cretaceous. Our figure represents the
common grey mullet (M. capita), one of several species frequenting the British
coasts. Although this mullet only grows to a weight of about 4 Ibs., some of
the foreign species may scale three times as much. This mullet has been
kept in a fresh- water pond, where it seemed to thrive better than in the sea.
The flesh of all the grey mullets is of good quality, but bears no comparison
to that of their red namesakes.

GAR-PIKE AND FLYING-FISH, Family SCOMBRESOCID&

In this place may be noticed a family in regard to the serial position of which
there is some difference of opinion, Dr. Gunther placing it among the tube-bladdered
fishes, while Professor Cope considers that its true position is here. The inclusion
of the group among the tube-bladdered fishes utterly spoils the definition of that
suborder, since in those members of the present family provided with an air-
bladder that organ lacks a duct. It is true that the fins of the flying-fishes and tln-ir
allies are less spiny than those of the more typical representatives of the suborder
under consideration, but, as we have seen, this character is one of but slight
morphological value. Agreeing with the preceding section in the abdominal
position of the pelvic fins, these fishes differ from those yet described, with the
exception of certain perches, in the union of the lower pharyngeal bones ; while
they are further characterised by the absence of a spinal dorsal fin, and the
deeply forked caudal. The single dorsal is situated opposite to the anal fin in the
caudal region, the air-bladder is generally present, the false gills are hidden and
glandular, and the simple stomach merely forms a dilatation of the intestinal tract.
Although the majority of the members of this family are marine, some being
pelagic, a few have taken to a fresh-water existence ; and while many of the latter
are viviparous, the whole of the others deposit eggs in the usual manner. 1 )is-
tributed over all the temperate and tropical seas, these fish are strictly carnivorous
in their habits. Geologically, the family is a comparatively ancient one, the g<:
pike being represented by an extinct species in the Sicilian Miocene, and by
allied extinct genus in the Eocene of Monte Bolca, while a fish nearly allied to
living flying-fishes occurs in the Cretaceous rocks of the Lebanon.

In North America it appears that the name " gar-pike " is applic
indifferently to a member of the present family, and to the v<
distinct fish also known as the bony pike ; but in scientific nomenclature it will
better to confine the term to the members of the present genus. Gar-pike ai
represented by nearly fifty species from temperate and tropical seas, among whk
the figured one (Belone vulgaris) is common on the British coasts, likewise ran*.
over the whole of the seas of Northern Europe, As a genus, these fishes
easily recognised by the production of the jaws into a long slender beak, formed
the upper one exclusively by the premaxillary bones; while they are furtl
characterised by the whole of the rays of the dorsal and anal fins being connect
by membrane. The beak is, however, only developed in the adult, very your
specimens having the jaws of normal form ; and it is not a little remarkable that



GAR-PIKE AND FLYING-FISH.



401



during their development the lower jaw becomes for a time much longer than the
upper one. Both jaws are beset with a number of rugosities, and likewise with a
series of long, conical teeth placed at considerable intervals. A peculiarity of
these tish is to be found in the green colour of their bones. Whereas the British
species does not exceed a couple of feet in length, some of the foreign repre-
sentatives of the genus may grow to as much as 5 feet. Dr. Gimther writes that,
skimming along the surface of the water, the gar-pike seize with their "long jaws
small tish, as a bird would seize them with its beak ; but their gullet is narrow, so
t they can swallow small fish only. They swim with an undulating motion of
body; but although they are in constant activity, their progress through the
ter is much slower than that of the mackerels, the shoals of which sometimes
ear simultaneously with them on our coasts." Frequently they may be seen
ing out of the water over small floating objects in sportive play, and when




GAR-PIKE (\ nat. size).

ick by the hook throw themselves above the surface in violent contortions,
le saury, or skipper (ticombresox saurus), is the British representative of a much
^nailer genus, differing from the gar-pikes by the minute size of the teeth, and
ikewise by the presence of a number of small finlets behind the dorsal and anal
ins. On the other hand, the half -beaks (H&mirka/mphus), some of which inhabit
'resh water, have the lower jaw larger than the upper throughout life.

Perhaps few sights are more pleasing during a long sea-voyage
in an ocean steamer than to stand in the bows and to watch the
lying-fish rising sometimes singly, but more frequently in larger or smaller
ihoals from beneath the vessel to take their beautiful flight over the crest of the
>vaves, till they once more disappear from view beneath the deep blue waters.
Represented by more than forty species from tropical and subtropical seas, the flying-
ishes, of which the common species (Exoccetus evolans) is shown in the illustration
m p. 314, form a genus which may be at once recognised by the great length of

VOL. V. 26



Flying-Fish.



402 SPINY-FINN ED GROUP.

the pectoral fins. They are further characterised by the blunt and short-jawed
head, and the moderately long oblong body invested in a coat of rather large-size* I
scales; the teeth, when present at all, being minute or rudimental. The ordinary
length of a flying-fish is from 10 inches to a foot, although specimens are
occasionally met with half as long again; and whereas the common form rank's
round the world, the distribution of some other species is extremely restricted, one
being recorded only from the seas on the Pacific side of the Isthmus of Panama.
The species differ considerably in the length of the pectoral fins ; those in which
they reach to the tail-fin being capable of taking the longest flights, whereas in
some others they do not extend beyond the anal. Associating in shoals, which are
sometimes of immense size, all these fish are pelagic in their habits, and all arc
capable of taking the skimming flight from which they derive their name. That
these fish take their flights primarily to escape from their enemies may be regarded
as certain ; and it is equally well ascertained that the continuance of the flight is
due to the original impetus of the leap from the water, and is not prolonged by
any flapping of the fins. From my own observations I am, however, of opinion
that the pectoral fins are vibrated rapidly on first leaving the water for a few
seconds, doubtless from a continuation of the swimming motion while in the
water, after which they become entirely motionless. During flight, the colour of
these fins may appear either white or brown, when seen from above, according to
the incidence of the light. So far as I have seen, flying-fish are unable to change
the direction of their course to any marked extent; but 011 this point, as will he



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 42 of 62)