NO. 1581. FISHES OFJAPAN—JORDAXAXDRICIIARDSOX. GCiS 



Family CEPHALACANTHID^. 



THE FLYING GURNARDS, 



Body elongate, subqiiadrangiilar, tapering behind ; head very blunt, 

 quadrangular, its surface almost entirely bony; nasals, preorbitals, 

 suborbitals, and bones of top of head united into a shield; nuchal 

 part of shield on each side produced backward in a bony ridge, ending 

 in a strong spine, which reaches past front of dorsal; interocular 

 space deeply concave; preorbitals forming a projecting roof above the 

 jaws; preopercle produced in a very long rough spine; cheeks and 

 opercles with small scales; opercle smaller than eye; gill openings 

 narrow, vertical, separated by a very broad, scaly isthmus; pseudo- 

 branchiae large; gill rakers minute; mouth small, lower jaw included; 

 jaws with granular teeth; no teeth on vomer or palatines; scales 

 bony, strongly keeled; 2 serrated, knife-like appendages at base of 

 tail; first dorsal of 4 or 5 rather high flexible spines, in some forms 

 preceded by 1 or more free spines; an immovable spine between the 

 dorsals; anal and second dorsal short, of slender rays; caudal small, 

 lunate; pectoral fins divided nearly to the base, into 2 parts, the 

 anterior portion about as long as the head, of about 6 rays, closely 

 connected; the posterior and larger portion more than twice length 

 of head, reaching nearly to caudal in the adult; much shorter in the 

 young; these rays very slender, simple, wide apart at tip; ventral 

 rays I, 4, the long fins pointed, their bases close together, the inner 

 rays shortest; air bladder with 2 lateral parts, each with a large 

 muscle; pyloric caeca numerous; vertebrae 9-1-13=22; myodome 

 undeveloped, the cranial cavity mostly closed in front by expansions 

 fi'om the subtectals, suturally connected with corresponding expan- 

 sions of the prootics and the parasphenoid ; prosethmoid and anteal 

 entirely disconnected, leaving a capacious rostral chamber opening 

 backward mesially into the interorbital region; infraorbital chain 

 with its second and third bones crowded out of the orbital margin 

 by junction of the first and fourth, and leaving a wide interval 

 between the suborbitals and preoperculum; the first very long and 

 extending backward, the second under the fourth, and the third 

 developed as a small special bone (pontinal) bridging the interval 

 between the second suborbital and the antero-interior angle of the 

 preoperculum; post-temporal suturally connected with the posterior 

 bones of the cranium, and with the upper surface forming a large 

 part of the roof of the head; intermaxillaries with well-developed 

 ascending pedicles gliding into the cavity between the anteal and 

 prosethmoids ; postero-temporal distant from the proscapula, and 

 manifest as an ossicle on the edge of the post-temporal. 



Warm seas, in both oceans ; 4 genera and 4 species known from the 

 waters of Japan. 



