Acanthonus, g. n. Ophidiid .

Head large and thick, armed in front and on the opercles with strong spines; trunk very short, the vent being below the pectoral; tail thin, strongly compressed, tapering, without caudal. Eye small. Mouth very wide, with the teeth in villiform bands in the jaws, on the vomer and palatine bones, and along the hyoid. Barbel none. Ventrals reduced to simple filaments, placed close together on the humeral symphysis. Gill-membranes not united. The gill-laminse are remarkably short, the gill-rakers long, lanceolate, stiff. Scales extremely small. Bones of the head soft.