The Head-fishes
BODY short and deep, or oblong, compressed, truncate behind, so that there is no caudal peduncle; skin rough, naked, spinous or tessellated; mouth very small, terminal; teeth completely united in each jaw, forming a bony beak without median suture; dorsal and anal fins similar, falcate in front, the posterior parts more or less confluent with the caudal fin; no spinous dorsal; no ventrals, pelvic bones undeveloped; pectoral fins present; belly not inflatable; gill-openings small, in front of the pectorals; an accessory opercular gill; no air-bladder.