Percichthys.—Differing from Perca especially in the number of the fin-spines, which are nine or ten in the first dorsal, and three in the anal fin. The upper surface of the head scaly.
These fishes represent the Freshwater Perches of the Northern Hemisphere in the fresh waters of the temperate parts of South America. Two species have been described from Patagonia, and one or two from Chili and Peru.
Labrax.—All the teeth are villiform, without canines; teeth on the palatine bones, vomer, and the tongue. Two dorsal fins, the first with nine spines; anal fin generally with three. Præoperculum serrated, and with denticulations along its lower limb; præorbital with the margin entire. Scales rather small. Branchiostegals seven; well developed pseudobranchiæ.
The “Bass” are fishes common on the coasts of Europe and the Atlantic coasts, and in the fresh waters of the United States and Canada. The three European species are almost exclusively inhabitants of the sea, entering brackish, but never fresh waters, whilst the American species, the number of which is still uncertain, seem to affect principally fresh water, although some are also found in the sea. The best known European species is Labrax lupus (see p. 41, Fig. [4]), common on the British coasts. It is a voracious fish, with a remarkably large stomach, and received from the ancient Romans the appropriate name of lupus. By the Greeks it was so highly esteemed that Archestratus termed this or one of the two other closely-allied species, taken near Milet, “offspring of the gods.” They attributed to it a tender regard for its own safety; and Aristotle says that it is the most cunning of fishes; and that, when surrounded by the net, it digs for itself a channel of escape through the sand. Specimens of from two to three feet are not scarce, but its flesh is nowadays much less esteemed than in ancient times. Of the North American species Labrax lineatus and Labrax rufus are the most common.
Lates.—All the teeth are villiform, without canines; teeth on the palatine bones and vomer, but none on the tongue. Two dorsal fins—the first with seven or eight, the anal fin with two or three, spines. Præoperculum with strong spines at the angle and the lower limb; also the præorbital is strongly serrated. Scales of moderate size. Branchiostegals seven; pseudobranchiæ present.
Three well-known species belong to this genus. The Perch of the Nile and other rivers of tropical Africa (Lates niloticus); the Perch of the Ganges and other East Indian rivers, which enters freely brackish water, and extends to the rivers of Queensland (Lates calcarifer). These two species attain to a large size, the Indian species to a length of five feet. Hamilton says that “the vulgar English in Calcutta call it ‘Cockup,’ and that it is one of the lightest and most esteemed foods brought to table in that city.” Specimens two feet in length and caught in salt water are by far the best quality. The third species (Lates colonorum) is found in Australia only, and does not appear to grow to the same large size as its congeners.
Allied to Lates is Psammoperca from Australia.
Percalabrax.—All the teeth villiform, without canines; teeth on the palatine bones and vomer, but none on the tongue. Two dorsal fins—the first with eleven, the anal fin with three spines. Præoperculum serrated along its hinder margin, and with strong spinous teeth below; præorbital not serrated. Scales rather small. Branchiostegals seven; pseudobranchiæ present.
This Perch (Percalabrax japonicus) is one of the most common fishes on the coasts of China, Japan, and Formosa; the Japanese name it “Zuzuki,” or “Seengo.”
Acerina.—All the teeth villiform, without canines; teeth on the vomer, but none on the palatine bones or the tongue. One continuous dorsal fin, of which the spinous portion consists of from thirteen to nineteen spines; two anal spines. Body rather low, with rather small scales. Bones of the skull with wide muciferous cavities; præoperculum denticulated.