OLIGORUS.--Body oblong, covered with small scales. Cleft of the mouth rather oblique, the lower jaw being the longer. Teeth villiform, without canines; teeth on the vomer and palatine bones. One dorsal, with eleven spines; anal with three; caudal fin rounded. Præoperculum with a single smooth or obtusely denticulated margin. To this genus belong two fishes well known on account of the excellent flavour of their flesh. The first (_O. macquariensis_) is called by the colonists “Murray-Cod,” being plentiful in the Murray River and other rivers of South Australia. It attains to a length of more than three feet, and to a weight of nearly 100 lbs. The second (_O. gigas_) is found in the sea, on the coast of New Zealand, and called by the Maoris and colonists “Hapuku.” Its average weight is about 45 lbs., but occasionally large specimens of more than a hundredweight are caught. At certain localities it is so plentiful that it may form an important article of trade. Dr. Hector, who has had opportunity of examining it in a fresh state, has pointed out anatomical differences from the Murray-Cod, from which it appears that it would be better placed in a distinct genus. [Illustration: Fig. 164.--The Murray-Cod, _Oligorus macquariensis_.] GRYSTES.--Body oblong, covered with scales of moderate size. All the teeth villiform, without canines; teeth on the vomer and palatine bones. One dorsal fin with ten spines; anal with three; caudal fin rounded. Præoperculum with a single smooth margin. One species, from the fresh waters of the United States (_G. salmonoides_), attains to a length of more than two feet. It is known by the name of “Growler,” and eaten. ARRIPIS.--Body oblong, covered with scales of moderate size. All the teeth villiform, without canines; teeth on the vomer and palatine bones. One dorsal fin, with nine slender spines; anal with three. Præoperculum denticulated. [Illustration: Fig. 165.--_Arripis salar_, South Australia.] Three species are known, from the coasts of Southern Australia and New Zealand. They are named by the colonists Salmon or Trout, from their elegant form and lively habits, and from the sport they afford to the angler. Their usual size is from 1 to 3 lbs., but specimens of double that weight are taken. The smaller specimens are the more delicate and better flavoured. When not fresh, they are liable to assume poisonous properties; and cases of poisoning are not unfrequently caused by them. HURO.--Body oblong, compressed, covered with scales of moderate size. All the teeth villiform; bones of the head without serrature. Mouth rather oblique, with the lower jaw projecting. Two dorsal fins, the first with six spines. The “Black Bass” of Lake Huron (_Huro nigricans_).