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depressed head is more or less fully armed with spines, and the body covered
with ctenoid scales ; the anterior spine of the first dorsal fin being isolated from ,
the rest, and teeth present on both the vomer and palatine bones. Day writes of
these fishes that " the wounds from their spines are dreaded because of the violent
irritation they occasion. Their eyes are peculiar; the iris possesses two semi-
circular flaps, one above, the other below, the upper being usually the larger; '
these flaps can be brought close together, probably under the stimulus of light."

Of a decidedly ugly appearance, the gurnards (Tri(ihi) are easilv
Gurnards.

recognised by their enormous, square, and elevated heads, m which

the upper surface and sides are entirely bony, and likewise by the finger-like
first three rays of the pectoral fins, which serve not only for walking on the ,
sea-bottom but likewise as organs of touch. There are two dorsal fins, of which the
spinous is tall, and the soft one long, low, and similar to the anal; the tail-tin
being slightly rounded. The teeth are villiform ; and the air-bladder, which is
generally furnished with lateral muscles, may be divided into two longitudinal
halves. They have been divided into three subgenera, of which the typical o
is characterised by the absence of teeth on the palatines, and the small size of t
scales, with the exception of the highly modified ones forming the lateral li
which are large, triangular, and spiny. The second group is distinguished by t
medium size of the scales; while in the third teeth are present on the palati
bones. Their colours are frequently brilliant, and the fins highly decorated.
The genus is represented by some forty species, distributed over all temperate and
tropical seas, out of which no less than seven are found in British waters. Their
flesh, which is firm and flaky, and of a pale orange-pink tinge, is extensively used
as food. One of the best known of the British species is the red gurnard (T. JH '//
which seldom exceeds 12 or 14 inches in length, and, when freshly caught, is
a bright red colour, with the sides and under-parts silvery white, and the
reddish white. Its food consists of crustaceans, which give the pinkish tinge to
its flesh, and the spawning-season is May or June. The sapphirine gurnard
(T. hirundo), which is the one represented in the woodcut, is another British
species, taking its Latin name from the length of the pectoral fins, and its English



ised



BULL-HEADS AND GURNARDS.



3*3



title from the beautiful azure tint of their inner surfaces. More abundant than
the other species, this gurnard may reach a couple of feet in length, its general
colour being brownish red. A third British form is commonly known as the piper
T. lyra), and may be recognised by the unusually large size of the head, the more
projecting muzzle, and the greater length of the spines of the gill-cover. The




SAPPHIRINE GURNARDS ( nat. size).

general colour is brilliant red, with the under-parts white. It attains a length of
li couple of feet, and is supposed to take its name from the grunting sound which,
Jin common with other species, it emits when first handled, owing to the escape
|of air through the mouth. The European forms are rarely found on the other side
tof the Atlantic, where their place is taken by representatives of the third subgenus.
Two British species are figured in the coloured Plate, namely, the grey gurnard
(T. gurnardus) above, and the streaked gurnard (T. lineata) below.



384 SPINY-PINNED GROUP.

Tin-: KI.VIXC (IruxARDs AND THEIR ALLIES, Family DACTYLOPTERIDJE.

Another family of the present section is typified by the so-called flying,
gurnards, and is easily recognised by the investiture of the body in an armour of
bony keeled plates or scales. In form the body is elongate and subcyclindrical ;
the teeth are weak ; and there is a bony stay connecting the preopercular with
the irifraorbital ring. These fishes are all marine, some being pelagic, and they
are found in all seas, from the Arctic Ocean to the Equator, as well as in the
Southern Hemisphere. They are represented by an extinct genus (Petalapteryx)
in the Italian middle Eocene

The curious-looking fish (Agonus cataphractus), figured in the

accompanying illustration, is the British representative of a genus

of small-sized fishes inhabiting the northern temperate seas and extending into




AHMED IUT.I.-HEAD (". n:it. size).

the Arctic Ocean. They are characterised by the angulation of the head and body,,
which are invested in bony plates; the small size of the teeth in the jaws: the-i
two dorsal fins ; and the absence of appendages to the pectorals. Of the armed \
bull-head, as the British species is popularly termed, Yarrell writes that it is not/I
'' uncommon along the line of our southern coast, where it is well known : and thw
young of small size are frequently taken by the shrimpers in most of the saiidyj
hays at the mouth of the Thames and of other rivers; on the eastern coast it
very plentiful It seldom exceeds 6 inches in length; its food is aquatic insect^
and crustaceans ; it spawns in May, depositing the ova among stones, and its flesh
is said to be firm and good." Somewhat curiously, an outlying representative Q\f.
the genus occurs on the Chilian coast.



BULL-HEADS AND GURNARDS.



385



Beaked As a genus remarkable for the singularity of their form, we may

Gurnards. briefly notice the beaked gurnards, of which the European representa-
tive (Peristetlius cataphractum) is shown in our illustration. These rather small
fishes are specially characterised by the preorbital bone being prolonged into a
flattened process projecting on each side beyond the muzzle ; the whole of the
squared head being invested in a solid bony case. Large plates of bone form the
body-armour ; the dorsal fin may be either continuous or divided into two moieties,
of which the second is the longer ; there are two free appendages in advance of
each pectoral fin; teeth are wanting; and the lower jaw is provided with barbels.
These fishes, of which there are some ten representatives, range from the southern
shores of Britain, through the Mediterranean and Atlantic, and likewise from the




BEAKED GURNARD ( J- nat. size).

Indian Ocean to China and the Sandwich Islands. Nowhere abundant, they are
jelieved to inhabit deeper water than the gurnards, which they resemble in their
reneral mode of life.

Flying Of more interest than either of the preceding are the so-called

Gurnards. flying gurnards (Dactylopterus) of the Mediterranean, the Tropical
Vtlantic, and Indo-Pacific Oceans, since they alone share with the true flying-



ish the power of taking long flying leaps along the surface of the sea. In order-
do this, their pectoral fins are greatly developed, assuming a wing-like form,

with the anterior portion shorter and separated from the remainder. The upper

surface and sides of the squared, gurnard-like head are bony ; long spines are present
n the scapular and preopercular ; the body is covered with medium -sized keeled
les, among which there is no lateral line ; and the second dorsal fin but slightly
xceeds the first in length. Although granular teeth are present on the jaw, the
alate is toothless. The air-bladder is divided into longitudinal halves, and
urnished with a muscle. It is only in the adult that the pectoral fins are suffi-

iently developed to enable these fishes to " fly." Of the three species, the best

VOL. V. 25



3 86



SPINY-FINNED GROUP,



Dragon-Fishes.



known is D. volitans, which may be commonly met with in the Mediterranean.

Very similar in their habits to the true flying-fish, the flying gurnards are more

heavily built, and measure as much as 18 inches in length.

In this place may be noticed the curious little dragon-fishes
(Pegasus), from the Indian, Chinese, and Australian seas, which

although referred by Dr. Giinther to a distinct family are included by Day in

the present one. In these strange little fishes the broad and depressed body is

covered witli bony
plates, which are
movable, although I

o

those investing the
tail are firmly
welded together.
The narrow jnll-



opening is situated
in front of the;
pectoral fin ; the
gill-cover is formed
of a single plate,
and the gills them-
selves are four in
number. The si i igle
short dorsal fin is
placed opposite ail
anal of similar




AUSTRALIAN DHAGON-FISH (uat. size).



size ; the pectorals are long, horizontal, and composed of simple rays, some of which
may bespinous; and the pelvis comprises one or two rays, the outer one being
elongated. Both teeth and an air-bladder are wanting. The figured species
(P. natans) is an Australian one, and is less well known than the Indian P. drai-o
and the Chinese P, volens\ dried specimens of the latter being familiar objects
on Chinese insect-boxes. Nothing seems to have been ascertained as to the habits
of these fish, although it has been suggested that they probably frequent sandy
shores. With this family we take leave of the great Cotta-Scombriform sectic
as it is called, and pass on to another containing only two or three families.



THE LUMP-SUCKERS, Family CYCLOPTERIDJE.

With the lump-suckers we come to a small section characterised by tl
spinous dorsal fin being short, and either composed of flexible spines, or mu<
less developed than the soft dorsal, or soft portion of the same ; the soft doi
being equal in extent to the anal. If present, the pelvic fins are either thoraci
or jugular in position, with one spine, and generally five (rarely four) soft ra;
There is a prominent papilla in the neighbourhood of the vent. In no case
there a bony stay to the preopercular from the infraorbital ring. As a family,
the lump-suckers are characterised by the thick or oblong body, which may be
either naked or tuberculated ; the small teeth ; and the presence of a circular



LUMP-SUCKERS.



387



idhesivo disc on tho lower surface of the chest, surrounded by a fringe of skin,
ml supported by the rudimental pelvic fins, the gill-opening being narrow. All
he members of the family, which are arranged under two genera, are carnivorous
md coast-dwelling fishes, restricted to the colder seas of the Northern Hemisphere,
nd ranging into the Arctic Ocean. They derive their name from their habit of
Attaching themselves to rocks by means of the adhesive disc.

The members of the typical genus Cyclopt&rus are ugly "lumpy" fishes, with
he thick, short body covered with a viscous tuberculated skin; the large head




I.I .Ml'-SUCKEH AND VIVIPAROUS RLENNY (J liat. size).



as a very short, blunted muzzle ; and there are rows of villiform teeth in the
iws, but none on the palate. Tho skeleton is remarkable for its softness, owing

the small amount of mineral matter entering into the composition of the bones.
n the British species (C. lumpua), represented in the upper figure of the accom-
anying illustration, the skin is so thick as to almost conceal the first dorsal fin ;
nd in the adult the large rough tubercles are arranged in four longitudinal series
n each side of the body. In the young, however, these tubercles are not developed.
Jthough these fishes may reach a length of a couple of feet, they do not usually
icasure more than 12 or 14 inches. Yarrell writes that " in the month of March

e colours of the lump-fish are in the highest perfection, combining various



*88 SPINY-PINNED GROUP.

shades of blue, purple, and rich orange." These voracious fishes feed chiefly on
the fry of other species. In the Arctic lump-sucker (C. spinosus) there are large,
conical bony plates, surmounted with a spine, on the head and body of the adult.
In the allied Liparis the skin is naked, and more or less loose.



THE GOBIES AND MUD-SKIPPERS, Family

The gobies and their allies differ from the preceding family in that there are
always distinct rays to the pelvic fins ; although in some cases the two fins may
be joined in the middle line. Elongated in form, the body may be either scaled
or naked; and the teeth are generally small, but may have enlarged tusks among




FRESH -WATER GOBY (nat. size).

them. The spinous portion of the dorsal (whether separate or continuous <
the soft dorsal) is always composed of flexible spines, and shorter than the
dorsal. The gill-opening is more or less narrowed, and there is usually no
bladder. This very extensive family comprises littoral fishes of small size
carnivorous habits, a few of which have accustomed themselves to a fresh-wat
life. It contains a large number of genera, some of which are extremely nuniri
in species, as are the latter in individuals ; and their range includes the cc
regions of all the temperate and tropical seas. Geologically, the group is
paratively ancient, true gobies dating from the middle Eocene of Monte Bol
while the extinct genus Ckirothrix occurs in the Chalk of the Lebanon.

Familiar to all in the person of the common British sj
Gobius niger, the gobies form a very large genus, with



Gobies.



GOBIES AND MUD-SKIPPERS, 389

geographical distribution as extensive as that of the family, but especially well
represented in tropical and subtropical seas, no less than forty different kinds
being recorded from those of India alone. These fishes have the body generally
scaled ; two dorsal fins, of which the first is usually furnished with six flexible
spines; the pelvic fins united to form a disc, which, however, is at most only
partially adherent to the abdomen ; the teeth in more than a single row ; and
the vertical gill-opening of moderate width. The form of the body is subject to
considerable specific variation ; and in some forms the head, and in others a part
or even the whole of the body is devoid of scales. In some cases there may be
barbels or warts on the head, and in others a crest on the occiput. There are
likewise considerable differences in the dentition, some species having large tusks
among the ordinary teeth. The gobies, of which there are several British marine
species, are especially partial to rocky coasts, where they protect themselves
against waves and storms by adhering to rocks by means of the sucker formed
by their modified pelvic fins ; many of them being often found in the swirl of the
retreating waves. Some, however, prefer brackish estuaries or lagoons, while
others again, like the Russian species (G. Jiuviatilis) represented in our illustration,
are exclusively fresh-water. In many of them the male constructs a nest in which
the spawn is hatched. In the case of the spotted goby, or polewig (G. minutus)
a species found for some distance up the Thames the male, when in tidal
pools, generally chooses one of the shells of a cockle or some other bivalve for its
nest ; the shell being placed on the sand with its concave surface downwards,
neath which the sand is hollowed out and cemented by a special mucilaginous
cretioii from the skin of the fish ; a cylindrical tunnel giving access to the nest,
d the whole structure being covered over with loose sand. The female having
eposited her eggs, which are fixed to the shell, in this nest, the male mounts
ard over them, maintaining his w T atch during the whole period of incubation,
hich lasts from six to nine days. A European goby (Latrunculus pellucidus),
longing to a distinct genus, and characterised by its translucent body, is
most peculiar among vertebrates in that its span of life is of only a year's
uration. In June and July the spawn is deposited, the eggs are hatched in
ugust, while in the late autumn or winter the fishes become fully mature ; these,
owever, die off in the following July or August, so that in September only the
ry are to be met with.

Omitting all mention of a number of more or less nearly allied
Mud- Skippers. T i

genera, our next representatives of the family are the mud -skippers

(PerioplitlLcdmus), remarkable not only for the peculiar physiognomy given them
by their conspicuous eyes, but likewise on account of their strange habits. These
fishes, which frequent the coasts and estuaries bordering the Indo-Pacific Ocean,
and likewise reappear on the shores of West Africa, take their name from their
prominent eyes, which are set close together somewhat below the line of the
profile, and are not only capable of protrusion and retraction but are furnished
with a well-developed outer eyelid. The elongate body is covered with cycloid
or slightly pectinated scales, extending on to the bases of the pectoral fins ; the
cleft of the mouth is nearly horizontal, with the upper jaw projecting somewhat
beyond the lower, and the conical teeth are vertical. The first dorsal fin includes



39



SPINY-FINNED GROUP.



a variable number of flexible spines; the base of the pectorals are muscular;
the pelvic fins are united for a portion of their length; and the caudal fin lias
its lower border obliquely truncated. The species here figured (P. koclrrn/rri)
has a wide range, being found in the Red Sea, the seas and on the coasts of India,
where it ascends tidal rivers and estuaries, as well as in the Andaman*, the Malay
Archipelago, and the islands of the Pacific. Concerning their habits, Day writes
that " these fishes, from the muscular development at the base of the pectoral
fins, are able to use them for progression on mud or for climbing. It is a most
curious sight to see P. schlosseri along the side of the Burmese rivers ; at a
distance the fishes appear like large tadpoles, stationary, contemplating all passing
objects, or else snapping at flies or other insects ; suddenly, startled by something,




MUD-SKIPPERS DISPORTING ( uat. size). After Hilgendorf.

away they go with a hop, skip, and a jump, either inland among the trees or on j
to the water like a flat stone or a piece of slate sent skimming by a schoolboy.
They climb on to trees and large pieces of grass, leaves, and sticks, holding on by
their pectoral fins exactly as if these were arms. Now and then they plant these ]
firmly as organs of support, the same as one places one's elbows on a table, then
they raise their heads and take a deliberate survey of surrounding objects." Of
certain allied species, which he places in a genus apart, the same writer remarks
that they are essentially mud-dwelling fish, and that if placed in a vessel of deep
water they appear to be rapidly drowned. In all, the remarkable prominence of the
eyes is more or less completely lost after death. On the slimy banks of the small
affluents of the Hughli near Calcutta, where the writer has often watched their
strange habits, these fishes may be seen in hundreds.



BLENNIES AND THEIR ALLIES 391

Concerning; the precise systematic position of the beautifully

Dragonets. x . /

coloured nsnes commonly known as dragonets ( Call 'ion ymus), there is

some difference of opinion ; Dr. Giinther placing them with the gobies, whereas
Day, on account of the wide separation of the pelvic fins (which in the latter and
their near allies either form a disc or are very close together), refers them to a
separate family. Be this as it may, these fishes, in addition to the feature already
mentioned, are characterised by the head and anterior portion of the naked body
being depressed, while the remainder is cylindrical. The pointed mouth has a
narrow horizontal cleft, and a very protractile upper jaw; the large eyes have a
more or less upward direction ; small teeth are present on the jaws, but none on the
palate ; and there is a strong spine at the angle of the preopercular. Of the two
dorsal fins, the foremost has from three to four flexible spines ; the pelvics are five-
rayed ; and the gill-opening is very narrow, and generally reduced to a perforation
on the upper border of the gill-cover, There is a large amount of sexual difference
among the dragonets, the adult males having the fin-rays produced into filaments
and the intervening membranes brightly coloured, whereas the females wear a
much more sombre livery ; and it is due to this variation that there were long
supposed to be two British representatives of the genus, namely, the gemmeous,
and the sordid dragonet ; the former being the male and the latter the female. In
the adult male of the common dragonet (C. lyra) the first dorsal spine is greatly
elongated; the general colour of the smooth skin being yellowish, beautifully
banded and spotted with lilac ; the first dorsal fin bearing several lilac spots, and
the second having lilac bands. In length, the male measures about 10 inches. The
yellow scalpin, as the male is called in some parts of Britain, is generally found
in comparatively deep water, whereas the female often approaches the margin of
the tide. Both sexes feed on molluscs and other hard-shelled creatures, as well as
on worms. Out of some thirty representatives, the majority are inhabitants of the
coast-regions of the temperate zone of the Old World, although a few are found in
the Tropical Pacific.

THE BLENNIES AND THEIR ALLIES, Families CEPOLID^E, BLENNIID^, etc.

The well-known blennies, together with five less important families, constitute
sectional group of spine-finned fishes, all of which may be treated under one
heading. As a group, these fishes are characterised by the body being in general
more or less nearly cylindrical in form ; the dorsal fin is elongated, and its spinous
portion, if distinct, is also long, being equal to or even exceeding the soft part in
length, while occasionally the whole fin may be spiny ; the anal is also more or less
elongate ; the pelvics, when present, are thoracic or jugular in position ; and the
caudal fin, which may be absent, is rounded or somewhat truncated.

The first family of the group (Cepolidoi) is represented by the
small marine band-fishes, of which one species (Cepola rubescens) is a
casual visitor to the British coasts. The essential characters of these fishes are to
be found in the elongate and band-like form of the body ; the presence of one spine
and five soft rays in the thoracically-placed pelvic fins ; and the absence of spines
in the single dorsal and anal fins. The eyes are rather large and lateral, the teeth



392



SPINY-PINNED GROUP.



of moderate size, and the caudal vertebra unusually numerous. While (lie
majority of these fishes are confined to the northern temperate seas, a few extend
into the Indian Ocean and as far south as Penang.

The remarkable fishes known as hairy-backs constitute another

Htiirv- Bucks

small family (Trichonotidce) distinguished from the last by tin-
jugular position of the pelvic fins, which are in front of the pectorals; there being
one or two spineless dorsal fins, an elongate anal fin, which is also spineless, and
no papillae in the neighbourhood of the vent. The typical genus is represented by
a single species (Trichonotus setiger) from the Oriental seas, characterised by the
first few rays of the single dorsal fin being isolated and more or less elongate, and
likewise by the lower jaw exceeding the upper in length. The New Zealand
thorny-nose (Hemerocoetes acanthorhynchus) represents a second genus, differing




NEW ZEALAND THORNY-NOSE.



Chirus.



from the last by all the rays of the long dorsal being in juxtaposition, by the up]
jaw being longer than the lower, and the presence of horny processes on tl
muzzle. These fishes are not unfrequently found floating on the surface of
ocean at a considerable distance from land.

The most remarkable representatives of a third small faniil
(Ckiridce) of this group constitute the genus Chinift, which is pn
in having several lateral lines, the number of these varying in the different spec-it
The family differs from the two preceding ones in that there is a bony stay cor
necting the preopercular with the infraorbital ring ; while it is further distinguish!
by the single dorsal having its spinous and soft portions of nearly equal lengtl
the anal being nearly equal in length to the soft dorsal, and the pelvies thoracic
position, with one spine and five rays. The compressed and oblong body is sc-alt
the cleft of the mouth lateral, and the teeth are weak. All the members of tl
family are small littoral fishes, inhabiting both sides of the Northern Pacific ; tl



BLENNIES.



393



Blennies.



igured species (Ckirus hexagrammus) being from Japanese waters. In the other
genera the lateral line is single.

The fourth family of the group (Blenniidcu) is much more
extensive than either of the others, comprising a considerable
lumber of genera, some of which are rich in species. The family agrees with the
miry-backs in the jugular position of the pelvic fins, which, when present at all,



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 41 of 62)