Fig. 170.—Scatophagus multifasciatus.
Scatophagus.—Two dorsal fins, united at the base, the first with ten or eleven spines; only the second is scaly. A recumbent spine before the dorsal, pointing forwards. Anal with four spines. Snout rather short. Præoperculum without spine. Scales very small.
Four species are known, from the Indian Ocean, of which S. argus is the most generally known, in fact, one of the most common Indian shore-fishes. It freely enters large rivers, and is said not to be particular in the selection of its food. The species figured (S. multifasciatus) represents S. argus on the coasts of Australia.
Fig. 171.—Bony enlargement of cranial bones of Ephippus. a, Enlargement of the frontal, and b, of the supraoccipital bones; c, interorbital septum; d, basis cranii. ⅓ nat. size.
Ephippus.—Snout short, with the upper profile parabolic. Dorsal fin deeply emarginate between the spinous and soft portions, the former with nine spines, the third of which is rather elongate, and flexible; spinous portion not scaly; anal spines three. Pectoral fin short. Præoperculum without spine. Scales of moderate size, or rather small.
Two or three species are known from the warmer parts of the Atlantic and Indian Oceans. The Atlantic species (E. faber) shows the remarkable peculiarity that in old specimens (12 and more inches long) the occipital crest, and sometimes some of the anterior neural and hæmal spines are enormously enlarged into a globular bony mass. This can hardly be regarded as a pathological change of the bone, as it has been found in all old specimens, without exception.
Drepane is allied to Ephippus, but has very long falciform pectoral fins. The single species D. punctata is common in the Indian Ocean and on the coasts of Australia. Hypsinotus, from Japan, appears to inhabit a greater depth than the other Squamipinnes.
Scorpis and Atypichthys are genera distinguished from the preceding by the presence of vomerine teeth. They belong to the coast-fauna of Australia, New Zealand, and Chili.