The Squirrel-fishes
BODY oblong or ovate, moderately compressed, covered with very strong ctenoid or spinous scales; head with large muciferous cavities; eyes lateral, very large; preorbital very narrow; mouth moderate, oblique; premaxillaries protractile; maxillary very large, with supplemental bone; bands of villiform teeth on jaws, vomer and palatines; opercular and membrane bones of head generally serrated or spinescent along their edges; branchiostegals 8; gillmembranes separate, free from the isthmus; pseudobranchiae present; no barbels; sides of head scaly; lateral line present; dorsal fin very long, deeply divided, with about 11 strong spines depressible in a scaly groove; anal with 4 spines, the third longest and strongest; ventrals thoracic, with one spine and 7 rays; caudal deeply forked, with sharp rudimentary rays or fulcra at base; vertebrae about 27; pyloric coeca 8 to 25; air-bladder large, sometimes connected with the organ of hearing. General colour red. Genera 4, species about 70, gaily-coloured inhabitants of tropical seas, abounding about coral reefs. Only 4 genera and about 12 species in our waters.
