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næus in the Amanitates Academica, vol. i. It is a very small species, native to Senegal and some other parts of Africa.

The great and almost inexhaustible class of fishes next demands our attention.

Our acquaintance with the laws which regulate the geographical distribution of this class is extremely meager: in other words, the facts illustrating the greater or less extension of their localities are few, and have never been properly generalized. From the immeasurable extent and continuous nature of the fluid which they inhabit, they are supplied by nature with greater facilities of dispersion than most other animals; while the greater equality of the temperature of water, when compared with that of either earth or air, admits, in several instances, of the same species inhabiting almost every latitude from pole to pole. Those races especially, which, travelling together in vast shoals, speedily consume the natural food which each particular spot affords, are obliged, like the pastoral tribes of old, or the woodland hunters of America, to remove from place to place in search of additional supplies, and thus the species acquires a more widely extended geographical distribution. It is thus that the cod and herring are spread over the whole extent of the Northern Ocean, and in undiminished numbers, notwithstanding the war of extermination which man and other voracious animals appear to wage against them. Those species which lead a solitary and, as it may be called, a stationary life are frequently confined within very narrow limits. The Chatodons, for example, which delight in rocky coasts covered with madrepores, attach themselves to the torrid zone, which produces so abundantly those magnificent ornaments of the sea. But though thus confined to particular spots, from which the individuals of the species never wander, the species itself may be said to be repeated again in different and distant regions, separated from each other by almost insurmountable obstacles. Thus, many of what may be termed stationary species are found identically the same along the coasts of Brazil, in the Arabian Gulf, and over the multiplied shores of Polynesia. It has hence been concluded that such species, incapable of colonizing them

selves by leaving their accustomed shores, and hazarding a journey across unknown oceans, have either been created in more places than one, or have been enabled to transport themselves by means different from any of those which are now available in the ordinary course of nature.*

If the natural means by which the more powerful species, inhabiting the saline waters of the ocean, have spread themselves from clime to clime, be in some measure within the reach of our comprehension, it is otherwise with those peculiar to rivers and the waters of inland lakes. How these have contrived to migrate from one region to another, and to people with identical species the depths of far-removed and solitary waters, separated from each other by chains of lofty mountains, or wide-extended wastes of desert sand, is a problem which, in the present state of our knowledge, we seek in vain to solve.†

It is the

Of the genus Muræna several species occur in the African seas. The spotted muræna (M. guttata) was observed by Forskall in the Red Sea. A small species of goby, scarcely exceeding an inch in length, is found in the Nile. Gobius aphya of Linnæus. We may here mention, that the name aphya, by which this species has been distinguished, seems to have been applied by the ancient writers to such small fishes as they vaguely supposed to have been produced rather from the foam of the ocean than according to the usual process of nature.‡ Several species of bull-head (Cottus) are described by Commerson, and the genus Scor pana, so eccentric in its forms, is represented in the African seas, among others, by the Cape scorpæna (S. Capensis), mentioned by Gronovius. A magnificent fish, called the opah dory (Zeus luna), inhabits the African shores. Dr. Mortimer exhibited a fish of this kind to the Royal Society in 1750, which was taken "on the coast of Leith ;" and he adds (in the Phil. Trans. for that year), that the Prince of Anamaboe, being then in England, immediately recognised it, and said it was common in his country, and was excellent eating.

* See Gaymard's Mémoire sur la Distribution Géographique des Poissons.

† See further on this subject the 5th number of my Illustrations of Zoology.

See Shaw's General Zoology, vol. v. p. 245

The Remora, so remarkable for its faculty of adhering to other fishes by a peculiar sucker-shaped organ on the top of its head, is found in the Mediterranean and other saline waters which wash the African shores. The olive-green remora (Echeneis cauda rotundata of Bloch) is common on the coasts of Mozambique. A species of Labrus (L. Niloticus) inhabits the Nile; and the star-eyed Bodian (Bodianus stellifer) is native to the seas about the Cape. The silvery mackarel (Scomber crumenophthalmus) is found in considerable plenty about the coasts of Guinea, and the Scomber chloris is also an African species.

The surmullet (Mullus ruber) so famous as an epicurean delicacy among the Romans, and so highly, though not very humanely, admired for the splendour of its dying hues, is found both along the African and European shores of the Mediterranean. "Vide," says Seneca, "quomodo exarserit rubor omni acrior minio! vide quas per latera venas agat! Ecce! sanguinem putes ventrem! quam lucidum quiddam cœruleumque sub ipso tempore effulsit! jam porrigitur et pallet, et in unum colorem componitur!" The flying gurnard (Trigla volitans) may likewise be mentioned as a Mediterranean species of singular habits and great beauty. It swims in shoals and delights the voyager by its short and frequent flights.

The electric silure (Silurus electricus) dwells in the rivers of Africa. It was observed by Forskall in the Nile, by whom, however, in his Fauna Arabica, it is improperly named Raja torpedo. Another species of Silurus called platte-kop, or flat-head, occurs in the fresh waters of Southern Africa. Mr. Burchell observed two boys of the Bushmen tribe fishing for this species. They stood by the water-side, motionless as herons. After waiting patiently for half an hour, a fish came within their reach, and was instantly pierced through with their spears or assagays. It was nearly three feet long, entirely of a lead colour, but approaching to white underneath. The head was very broad and flat, the eyes pale yellow and extremely small, and the mouth was bearded with several very long strings. The flesh was white, rich, and nutritious. This fish seems to occur only in those rivers which run to the western coast (that is, to the northward of the Cape of Good Hope), while, on the other hand, eels have never been seen in any but those which fall into the ocean eastward of that cape.

Of the salmon genus, the Salmo fulvus, a fierce and hungry fish, is much esteemed as an article of food by the inhabitants of Guinea. The notable genus Polypterus was first scientifically distinguished by M. Geoffroy. Its shape is long, cylindrical, and serpentiform; the head is defended by large bony plates; and the body is covered by strong scales, resembling those of a coat of mail. This fish is called bichin by the Egyptians, and is considered as very rare. It is said to dwell in the soft mud of the Nile, and is the finest flavoured of all the Nilotic fishes; but as it is hardly possible to open the skin with a knife, the fish is first boiled, and the skin afterward drawn off almost entire. The tooth-tongued argentine (A. Glossodonta) is a beautiful species, native to the Red Sea; and the pearl-bladdered argentine (A. Sphyraena) is a Mediterranean fish of the same genus. The air-bladder of this species is equally bright and beautiful with its external parts, and along with these is much used in the preparation of artificial pearls.

The flying-fish (Exocatus exiliens) is remarkable for the great length of its pectoral fins, which enable it to sustain itself above the waves for several hundred yards. The silvery polyneme (P. Niloticus) is a very elegant fish, of great excellence as an article of food. Its mode of capture in the Nile is described by Bruce. The ten-fingered polyneme (P. decadactylus), likewise esteemed a very wholesome and agreeable fish, occurs along the coasts of Guinea, and occasionally enters the rivers of that country. Of fishes allied to the herring, Africa produces several species. The Clupea Africana is said to be extremely plentiful during the summer months in the last-named district; and the dorab herring (C. dorab) is described by Forskall as native to the Red Sea. Among the carp tribe we shall merely mention the Cyprinus gonorhynchus, mentioned by Gronovius as an inhabitant of the Cape seas. We may observe in passing, that a great variety of fish are caught in the salt waters which environ the Cape; but fresh fish are there so rare, that Mr. Burchell "does not recollect having seen any at table except eels, and these were regarded as a curiosity."* The genus Mormyrus seems almost entirely peculiar to the Nile.

Of the cartilaginous fishes, several species of ray inhabit *Travels, vol. i. p. 79.

the African seas. For example, the Raja guttata was seen by Commerson along the coasts of Madagascar, and the lymna and pearled rays (R. lymna and sephen) both occur in the Red Sea. It is from the skin of the last-named species that the beautiful substance called Galluchat by the French is prepared. It is tinted with blue, green, or red, according to the taste of the artist, and being afterward polished, is used in the manufacture of different kinds of cases, telescope-tubes, &c. The younger specimens, according to La Cépède, are preferred, the tubercular coat of the full-grown individuals being rather too rough for the desired purpose. Several species of shark inhabit the African seas. They are disagreeable to bathers.

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The extraordinary genus Ostracion, or trunk-fish, distinguished by the peculiar bony crust or covering in which it is enveloped, is widely distributed over the Indian and American oceans. Of the African species we may name the tuberculated trunk-fish (C. tuberculatus), by some regarded a mere variety of Ostracion triqueter, a kind much esteemed for the uses of the table in the East Indies. The not less remarkable tribe included in the genus Tetrodon are represented in Africa by the lineated species (T. lineatus) which sometimes occurs in the Nile, where Hasselquist was assured by the fishermen, that on seizing this fish in the water their hands were frequently stung as if by nettles.

The last genus to which we shall allude is that called Syngnathus, or pipe-fish. Some of these are found in the northern seas, others in the equatorial; while the most remarkable of all is the foliated pipe-fish (Hippocampus fohiatus, Cuvier), which has hitherto occurred only along the shores of New-Holland and Van Dieman's Land. The pelagic pipe-fish (S. pelagicus) is found in the African seas.

We shall close our ichthyological department by two short extracts. "I was present," says M. Adanson, "at a very extraordinary capture of fish, made the same month (March, 1750) on the coast of Ben, within a league of the island Goree, by the company belonging to one of the East India ships, which had anchored in the road. They had only a net of about sixty fathoms, which they threw at a venture into the sea; for they were not so lucky as to espy any of those shoals of fishes: yet they had such surprising

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