Fifteen species of small size, from the shores of the tropical and sub-tropical zones. The species figured on p. 42, Fig. 5, occurs on the north-west coast of Australia and in Japan.

Deep-sea fishes, obtained in the Pacific at depths varying from 1100 to 2400 fathoms. The largest example is twenty inches long. Two species.

This very singular form is one of the discoveries of the “Challenger;” it is widely distributed over the seas of the Southern Hemisphere, in depths varying from 520 to 2600 fathoms. The elongate pectoral rays are most probably organs of touch. Four species were discovered, the largest specimen being thirteen inches long.

Two species only are known of this singular genus; both are evidently inhabitants of considerable depths, and periodically come nearer to the surface. One (H. nehereus) is well known in the East Indies, being of excellent flavour. When newly taken its body is brilliantly phosphorescent. When salted and dry it is known under the names of “Bombay-ducks” or “Bummaloh,” and exported in large quantities from Bombay and the coast of Malabar. The second species (H. microchir) exceeds the other in length, and has been found in the sea off Japan.

The fishes of this genus are small, of truly pelagic habits, and distributed over all the temperate and tropical seas; they are so numerous that the surface-net, when used during a night of moderate weather, scarcely ever fails to enclose some specimens. They come to the surface at night only; during the day and in very rough weather they descend to depths where they are safe from sunlight or the agitation of the water. Some species never rise to the surface; indeed, Scopeli have been brought up in the dredge from almost any depth to 2500 fathoms. Thirty species are known. Gymnoscopelus differs from Scopelus in lacking scales.

This singular genus, one of the “Challenger” discoveries, is known from four examples, obtained at depths varying between 1600 and 2150 fathoms, off the coast of Brazil, near Tristan d’Acunha and north of Celebes. All belong to one species, I. murrayi. The eye seems to have lost its function of vision and assumed that of producing light. The specimens are from 4 to 5½ inches long.

Three species; small pelagic fishes from the Mediterranean and Atlantic.—Sudis, from the Mediterranean, has a dentition slightly different from that of Paralepis.

This is one of the largest and most formidable deep-sea fishes. One species only is well known, P. ferox, from Madeira and the sea off Tasmania; other species have been noticed from Cuba and the North Pacific, but it is not evident in what respects they differ specifically from P. ferox. This fish grows to a length of six feet, and from the stomach of one example have been taken several Octopods, Crustaceans, Ascidians, a young Brama, twelve young Boar-fishes, a Horse-mackerel, and one young of its own species. The stomach is coecal; the commencement of the intestine has extremely thick walls, its inner surface being cellular, like the lung of a reptile; a pyloric appendage is absent. All the bones are extremely thin, light, and flexible, containing very little earthy matter; singular is the development of a system of abdominal ribs, symmetrically arranged on both sides, and extending the whole length of the abdomen. Perfect specimens are rarely obtained on account of the want of coherence of the muscular and osseous parts, caused by the diminution of pressure when the fish reaches the surface of the water. The exact depth at which Plagyodus lives is not known; probably it never rises above a depth of 300 fathoms.

The other less important genera belonging to this family are Aulopus, Chlorophthalmus, Scopelosaurus, Odontostomus, and Nannobrachium.

Third Family—Cyprinidæ.

Body generally covered with scales; head naked. Margin of the upper jaw formed by the intermaxillaries. Belly rounded, or, if trenchant, without ossifications. No adipose fin. Stomach without blind sac. Pyloric appendages none. Mouth toothless; lower pharyngeal bones well developed, falciform, sub-parallel to the branchial arches, provided with teeth, which are arranged in one, two, or three series. Air-bladder large, divided into an anterior and posterior portion by a constriction, or into a right or left portion, enclosed in an osseous capsule. Ovarian sacs closed.

The family of “Carps” is the one most numerously represented in the fresh waters of the Old World and of North America. Also numerous fossil remains are found in tertiary freshwater-formations, as in the limestones of Oeningen and Steinheim, in the lignites of Bonn, Stöchen, Bilin, and Ménat, in the marl slates and carbonaceous shales of Licata in Sicily, and of Padang in Sumatra, in corresponding deposits of Idaho in North America. The majority can be referred to existing genera: Barbus, Thynnichthys, Gobio, Leuciscus, Tinca, Amblypharyngodon, Rhodeus, Cobitis, Acanthopsis, only a few showing characters different from those of living genera: Cyclurus, Hexapsephus, Mylocyprinus (tertiary of North America).

Most Carps feed on vegetable and animal substances; a few only are exclusive vegetable feeders. There is much less diversity of form and habits in this family than in the Siluroids; however, the genera are sufficiently numerous to demand a further subdivision of the family into groups.

I. Catostomina.—Pharyngeal teeth in a single series, exceedingly numerous and closely set. Dorsal fin elongate, opposite to the ventrals; anal short, or of moderate length. Barbels none.

These fishes are abundant in the lakes and rivers of North America, more than thirty species having been described, and many more named, by American ichthyologists. Two species are known from North-Eastern Asia. They are generally called “Suckers,” but their vernacular nomenclature is very arbitrary and confused. Some of the species which inhabit the large rivers and lakes grow to a length of three feet and a weight of fifteen pounds. The following genera may be distinguished:—Catostomus, “Suckers,” “Red-horses,” “Stone-rollers,” “White Mullets;” Moxostoma; Sclerognathus, “Buffaloes,” “Black Horses;” and Carpiodes, “Spear-fish,” “Sail-fish.”

II. Cyprinina.—Anal fin very short, with not more than five or six, exceptionally seven, branched rays. Dorsal fin opposite ventrals. Abdomen not compressed. Lateral line running along the median line of the tail. Mouth frequently with barbels, never more than four in number. Pharyngeal teeth generally in a triple series in the Old World genera; in a double or single series in the North American forms, which are small and feebly developed. Air-bladder present, without osseous covering.

The “Carp” (C. carpio, “Karpfen,” “La carpe,”) is originally a native of the East, and abounds in a wild state in China, where it has been domesticated for many centuries; thence it was transported to Germany and Sweden, and the year 1614 is assigned as the date of its first introduction into England. It delights in tranquil waters, preferring such as have a muddy bottom, and the surface partially shaded with plants. Its food consists of the larvæ of aquatic insects, minute testacea, worms, and the tender blades and shoots of plants. The leaves of lettuce, and other succulent plants of a similar kind, are said to be particularly agreeable to them, and to fatten them sooner than any other food. Although the Carp eats with great voracity when its supply of aliment is abundant, it can subsist for an astonishing length of time without nourishment. In the winter, when the Carps assemble in great numbers, and bury themselves among the mud and the roots of plants, they often remain for many months without eating. They can also be preserved alive for a considerable length of time out of the water, especially if care be taken to moisten them occasionally as they become dry. Advantage is often taken of this circumstance to transport them alive, by packing them among damp herbage or damp linen; and the operation is said to be unattended with any risk to the animal, especially if the precaution be taken to put a piece of bread in its mouth steeped in brandy!

The fecundity of these fishes is very great, and their numbers consequently would soon become excessive but for the many enemies by which their spawn is destroyed. No fewer than 700,000 eggs have been found in the ovaries of a single Carp, and that, too, by no means an individual of the largest size. Their growth is very rapid, more so perhaps than that of any other Freshwater fish, and the size which they sometimes attain is very considerable. In certain lakes in Germany individuals are occasionally taken weighing thirty or forty pounds; and Pallas relates that they occur in the Volga five feet in length, and even of greater weight than the examples just alluded to. The largest of which we have any account is that mentioned by Bloch, taken near Frankfort-on-the-Oder, which weighed seventy pounds, and measured nearly nine feet in length,—a statement the accuracy of which is very much open to doubt.

Like other domesticated animals the Carp is subject to variation; some individuals, especially when they have been bred under unfavourable circumstances, have a lean and low body; others are shorter and higher. Some have lost every trace of scales, and are called “Leather-carps;” others retain them along the lateral line and on the back only (“Spiegelkarpfen” of the Germans). Finally, in some are the fins much prolonged, as in certain varieties of the Gold-fish. Cross-breeds between the Carp and the Crucian Carp are of common occurrence. The Carp is much more esteemed as food in inland countries than in countries where the more delicate kinds of sea fishes can be obtained.

Two well-known species belong to this genus. The “Crucian Carp” (C. carassius, “Karausche”) is generally distributed over Central and Northern Europe, and extends into Italy and Siberia. It inhabits stagnant waters only, and is so tenacious of life that it will survive a lengthened sojourn in the smallest pools, where, however, it remains stunted; whilst in favourable localities it attains to a length of twelve inches. It is much subject to variation of form; very lean examples are commonly called “Prussian Carps.” Its usefulness consists in keeping ponds clean from a super-abundance of vegetable growth, and in serving as food for other more esteemed fishes. The second species is the “Gold-fish,” Carassius auratus. It is of very common occurrence in a wild state in China and the warmer parts of Japan, being entirely similar in colour to the Crucian Carp. In a domesticated state it loses the black or brown chromatophors, and becomes of a golden-yellow colour; perfect Albinos are comparatively scarcer. Many varieties and monstrosities have been produced during the long period of its domestication; the variety most highly priced at present being the so-called “Telescope-fish,” of which a figure is annexed. The Gold-fish is said to have been first brought to England in the year 1691, and is now distributed over nearly all the civilised parts of the world.

The “Catla” (C. buchanani), one of the largest Carps of the Ganges, growing to a length of more than three feet, and esteemed as food.

About thirteen species are known from rivers of tropical Africa and the East Indies.

A small fish (D. lamta), extremely abundant in almost all the mountain streams from Abyssinia and Syria to Assam.

Characteristic of the fauna of Western Asia; one species from Abyssinia. Of the fifteen species known C. damascina deserves to be specially mentioned, being abundant in the Jordan and other rivers of Syria and Asia Minor.

No other genus of Cyprinoids is composed of so many species as the genus of “Barbels,” about 200 being known from the tropical and temperate parts of the Old World; it is not represented in the New World. Although the species differ much from each other in the form of the body, number of barbels, size of the scales, strength of the first dorsal ray or spine, etc., the transition between the extreme forms is so perfect that no further generic subdivision should be attempted. Some attain a length of six feet, whilst others never exceed a length of two inches. The most noteworthy are the large Barbels of the Tigris (B. subquincunciatus, B. esocinus, B. scheich, B. sharpeyi); the common Barbel of Central Europe and Great Britain (B. vulgaris); the “Bynni” of the Nile (B. bynni); B. canis from the Jordan; the “Mahaseer” of the mountain streams of India (B. mosal), probably the largest of all species, the scales of which are sometimes as large as the palm of a hand. The small, large-scaled species are especially numerous in the East Indies and the fresh waters of Tropical Africa.

Three species from the East Indies.

Three species from mountain streams of the Himalayas.

Seventeen species are known from fresh waters of the Himalayas, and north of them. Other genera from the same region, and with the anal sheath, are Ptychobarbus, Gymnocypris, Schizopygopsis, and Diptychus.

The “Gudgeons” are small fishes of clear fresh waters of Europe; they are, like the barbels, animal feeders. In Eastern Asia they are represented by two closely allied genera, Ladislavia and Pseudogobio.

About ten species are known from North America; they are small, and called “Chub” in the United States. C. biguttatus is, perhaps, the most widely-diffused Freshwater-fish in the United States, and common everywhere. Breeding males have generally a red spot on each side of the head.

Other similar genera from the fresh waters of North America, and generally called “Minnows,” are Pimephales (the “Black Head”), Hyborhynchus, Hybognathus, Campostoma (the “Stone-lugger”), Ericymba, Cochlognathus, Exoglossum (the “Stone Toter” or “Cut-lips”), and Rhinichthys (the “Long-nosed Dace”).

The remaining Old World genera belonging to the group Cyprinina are Cirrhina, Dangila, Osteochilus, Barynotus, Tylognathus, Abrostomus, Crossochilus, Epalzeorhynchus, Barbichthys, Amblyrhynchichthys, Albulichthys, Aulopyge, Bungia, and Pseudorasbora.

III. Rohteichthyina.—Anal fin very short, with not more than six branched rays. Dorsal fin behind ventrals. Abdomen compressed. Lateral line running along the median line of the tail. Mouth without barbels. Pharyngeal teeth in a triple series.

One genus and species only, Rohteichthys microlepis, from Borneo and Sumatra.

IV. Leptobarbina.—Anal fin very short, with not more than six branched rays. Dorsal fin opposite to ventrals. Abdomen not compressed. Lateral line running in the lower half of the tail. Barbels present, not more than four in number. Pharyngeal teeth in a triple series.

One genus and species only, Leptobarbus hoevenii, from Borneo and Sumatra.

V. Rasborina.—Anal fin very short, with not more than six branched rays. Dorsal fin inserted behind the origin of the ventrals. Abdomen not compressed. Lateral line running along the lower half of the tail, if complete. Mouth sometimes with barbels, which are nevermore than four in number. Pharyngeal teeth in a triple, or single series. Air-bladder present, without osseous covering.

Thirteen species of small size from the East Indian Continent and Archipelago, and from rivers on the east coast of Africa.

Three species of small size from the Continent of India.

To the same group belong Luciosoma, Nuria, and Aphyocypris, from the same geographical region.

VI. Semiplotina.—Anal fin short, with seven branched rays, not extending forwards to below the dorsal. Dorsal fin elongate, with an osseous ray. Lateral line running along the middle of the tail. Mouth sometimes with barbels.

Two genera: Cyprinion, from Syria and Persia, and Semiplotus from Assam.

VII. Xenocypridina.—Anal fin rather short, with seven or more branched rays, not extending forwards to below the dorsal fin. Dorsal short, with an osseous ray. Lateral line running along the middle of the tail. Mouth sometimes with barbels. Pharyngeal teeth in a triple or double series.

Three genera: Xenocypris and Paracanthobrama from China; and Mystacoleucus from Sumatra.

VIII. Leuciscina.—Anal fin short or of moderate length, with from eight to eleven branched rays, not extending forwards to below the dorsal. Dorsal fin short, without osseous ray. Lateral line, if complete, running along, or nearly in, the middle of the tail. Mouth generally without barbels. Pharyngeal teeth in a single or double series.

The numerous species of this genus are comprised under the name of “White-fish;” they are equally abundant in the northern temperate zone of both hemispheres, about forty species being known from the Old World, and about fifty from the New. The most noteworthy species of the former Fauna are the “Roach” (L. rutilus, see Fig. 21, p. 50), common all over Europe north of the Alps; the “Chub” (L. cephalus), extending into Northern Italy and Asia Minor; the “Dace” (L. leuciscus), a companion of the Roach; the “Id” or “Nerfling” (L. idus), from the central and northern parts of Continental Europe, domesticated in some localities of Germany, in this condition assuming the golden hue of semi-albinism, like a Gold-fish, and then called the “Orfe;” the “Rudd,” or “Red-eye” (L. erythrophthalmus), distributed all over Europe and Asia Minor, and distinguished by its scarlet lower fins; the “Minnow” (L. phoxinus), abundant everywhere in Europe, and growing to a length of seven inches in favourable localities. The North American species are much less perfectly known; the smaller ones are termed “Minnows,” the larger “Shiner” or “Dace.” The most common are L. cornutus (Red-fin, Red Dace); L. neogæus, a minnow resembling the European species, but with incomplete lateral line; L. hudsonius, the “Spawn-eater” or “Smelt.”

Only one species of “Tench” is known (T. tinca), found all over Europe in stagnant waters with soft bottom. The “Golden Tench” is only a variety of colour, an incipient albinism like the Gold-fish and Id. Like most other Carps of this group it passes the winter in a state of torpidity, during which it ceases to feed. It is extremely prolific, 297,000 ova having been counted in one female; its spawn is of a greenish colour.

A North American genus, to which belong some of the most common species of the United States. L. pulchellus (the “Fall-fish,” “Dace,” or “Roach”), one of the largest White-fishes of the Eastern States, attaining to a length of 18 inches, and abundant in the rapids of the larger rivers. L. corporalis (the “Chub”), common everywhere from New England to the Missouri region.

Seven species from the Continent of Europe and Western Asia.

Other Old World genera belonging to the Leuciscina are Myloleucus, Ctenopharyngodon, and Paraphoxinus; from North America: Mylopharodon, Meda, Orthodon, and Acrochilus.

IX. Rhodeina.—Anal fin of moderate length, with from nine to twelve branched rays, extending forwards to below the dorsal. Dorsal fin short, or of moderate length. Lateral line, if complete, running along or nearly in the middle of the tail. Mouth with very small, or without any barbels. Pharyngeal teeth in a single series.

Very small roach-like fishes inhabiting chiefly Eastern Asia and Japan, one species (Rh. amarus) advancing into Central Europe. The thirteen species known have been distributed among four genera, Achilognathus, Acanthorhodeus, Rhodeus, and Pseudoperilampus. In the females a long external urogenital tube is developed annually during the spawning season. The European species is known in Germany by the name of “Bitterling.”

X. Danionina.—Anal fin of moderate length or elongate, with not less, and generally more, than eight branched rays. Lateral line running along the lower half of the tail. Mouth with small, or without any, barbels. Abdomen not trenchant. Pharyngeal teeth in a triple or double series.

Small fishes from the East Indian Continent, Ceylon, the East Asiatic Islands, and a few from East African Rivers, The genera belonging to this group are Danio, Pteropsarion, Aspidoparia, Barilius, Bola, Scharca, Opsariichthys, Squaliobarbus, and Ochetobus: altogether about forty species.

XI. Hypophthalmichthyina.—Anal fin elongate. Lateral line running nearly along the median line of the tail. Mouth without barbels. Abdomen not trenchant. No dorsal spine. Pharyngeal teeth in a single series.

One genus (Hypophthalmichthys) with two species from China.

XII. Abramidina.—Anal fin elongate. Abdomen, or part of the abdomen, compressed.

The “Breams” are represented in the temperate parts of both northern hemispheres; in Europe there occur the “Common Bream,” A. brama; the “Zope,” A. ballerus; A. sapa; the “Zärthe,” A. vimba; A. elongatus; the “White Bream,” A. blicca; A. bipunctatus. Of these A. brama and A. blicca are British; the former being one of the most common fishes, and sometimes attaining to a length of two feet. Crosses between these two species, and even with other Cyprinoids, are not rare. Of the American species A. americanus (“Shiner,” “Bream”) is common and widely distributed; like the European Bream it lives chiefly in stagnant waters or streams with a slow current.

Four species from Eastern Europe to China.

“Bleak” are numerous in Europe and Western Asia, fifteen species being known. The common Bleak (A. alburnus) is found north of the Alps only, and represented by another species (A. alburnellus, “Alborella,” or “Avola”) in Italy.

Of the other genera referred to this group, Leucaspius and Pelecus belong to the European Fauna; Pelotrophus is East African; all the others occur in the East Indies or the temperate parts of Asia, viz. Rasborichthys, Elopichthys, Acanthobrama (Western Asia), Osteobrama, Chanodichthys, Hemiculter, Smiliogaster, Toxabramis, Culter, Eustira, Chela, Pseudolabuca, and Cachius.

XIII. Homalopterina.—Dorsal and anal fins short, the former opposite to ventrals. Pectoral and ventral fins horizontal, the former with the outer rays simple. Barbels six or none. Air-bladder absent. Pharyngeal teeth in a single series, from ten to sixteen in number.

Inhabitants of hill-streams in the East Indies; they are of small size and abundant where they occur. Thirteen species are known belonging to the genera Homaloptera, Gastromyzon, Crossostoma, and Psilorhynchus.

XIV. Cobitidina.—Mouth surrounded by six or more barbels. Dorsal fin short or of moderate length; anal fin short. Scales small, rudimentary, or entirely absent. Pharyngeal teeth in a single series, in moderate number. Air-bladder partly or entirely enclosed in a bony capsule. Pseudobranchiæ none: Loaches.

Four species from Europe and Asia. M. fossilis is the largest of European Loaches, growing to a length of ten inches; it occurs in stagnant waters of eastern and southern Germany and northern Asia. In China and Japan it is replaced by an equally large species, M. anguillicaudatus.

The greater number of Loaches belong to this genus; about fifty species are known from Europe and temperate Asia; such species as extend into tropical parts inhabit streams of high altitudes. Loaches are partial to fast-running streams with stony bottom, and exclusively animal feeders. In spite of their small size they are esteemed as food where they occur in sufficient abundance. The British species, N. barbatulus, is found all over Europe except Denmark and Scandinavia.