Fig. 401.—Hoplopteryx lewesiensis. (Restored by A. S. Woodward.)
Fossil genera: Sphenocephalus, Acrogaster, Pycnosterinx, Hoplopteryx, from the Upper Cretaceous. Asineops, from the Eocene of North America, is supposed to be allied to Aphredoderus. Beryx is represented by several species in the Upper Cretaceous, and Holocentrum occurs in the Eocene and Miocene.
Fam. 2. Monocentridae.—The single genus Monocentris, with two species, one from the seas of Japan, China, and India, and one from the South Pacific, is very nearly related to the Berycidae, but differs in the absence of ribs on the anterior six vertebrae, in the very large bony scales, forming together a coat of mail, and in the structure of the ventral fin, which is reduced to a strong spine and two or three very short soft rays. The spines of the dorsal fin are very strong and isolated.
Fam. 3. Pempheridae.—The resemblance which the fishes united under this family bear to Beryx is very striking, and applies to the skeleton as well as to the external characters. But the ventral fins are formed of one spine and five soft rays, as in most Acanthopterygians. Bathyclupea agrees with Beryx in being possessed of an open duct to the air-bladder. About twelve species are known, referable to four genera: Pempheris, Parapriacanthus, Neopempheris, from the Indian, Pacific, and tropical Atlantic Oceans, and the deep-sea Bathyclupea, from the Indian and Caribbean Seas, at depths of 145 to 419 fathoms.
Fig. 402.—Pempheris muelleri. (After Jordan and Evermann.)
Fam. 4. Centrarchidae.—No subocular lamina of the suborbitals, or subocular shelf; entopterygoid present; palate toothed; teeth conical. Praecaudal vertebrae with transverse processes from the third or fourth to the last; ribs mostly sessile, behind the transverse processes. Two nostrils on each side. Gill-membranes free from isthmus; 5 to 7 branchiostegal rays; gills 4, a slit behind the fourth; pseudobranchiae more or less developed, often rudimentary or absent. Lower pharyngeal bones separate. Soft portion of dorsal fin not more developed than the anal. Carnivorous freshwater fishes, some entering brackish water. Many are known to build nests. Mostly inhabitants of North America, the best known being the Sun-Fishes (Lepomis), and Black Bass (Micropterus), several species of which have recently been introduced into continental Europe. Principal genera: Pomoxys, Centrarchus, Ambloplites, Chaenobryttus, Micropterus, Lepomis, Elassoma, Kuhlia. Thirty-two species are known.
Fam. 5. Cyphosidae.—Herbivorous fishes, agreeing in their essential osteological characters with the preceding, differing in the incisor-like outer teeth and densely-scaled fins. Some 14 species are known, from the Pacific and Indian Oceans, referable to 4 genera: Cyphosus (Pimelepterus), Hermosilla, Sectator, Medialuna.
Fam. 6. Lobotidae.—As in Centrarchidae, but transverse processes of vertebrae very short, and palate toothless. Two genera: Lobotes, with two species from the warm parts of the Indian and Pacific Oceans, the Mediterranean, and the Atlantic coast of America, and Datnioides, with two species from the estuaries of the Ganges and the rivers of Burma, Siam, and the Malay Peninsula and Archipelago.