24 HOLOCEPHALI. 



SUBCLASS HOLOCEPHALI. 



This group, defined on page 13, is equivalent to the 



ORDER VI. HOLOCEPHAI,!. 



Skeleton cartilaginous ; gill cavity with four clefts within, but 

 externally with a single opening, which is covered by a fold of skin 

 within which is a rudimentary opercle. Xo spiracles. Jaws with- 

 out separate teeth, but armed with bony plates. Notochord persist- 

 ent, the vertebrae consisting of rings around a notochordal sheath. 

 No air-bladder ; intestine with a spiral valve ; skin smooth, with a 

 highly developed mucous system. Dorsal fin with a strong spine. 

 One family. (6Xos, solid ; <f(f)aXrj, head.) 



FAMILY XIX. CHIM^ERID^J. 



Forehead of males with a movable cartilaginous hook, turned 

 forward and armed with prickles at tip. Oviparous, the egg- 

 cases elliptical, with silky filaments. Two genera, 5 or 6 species, 

 in cold waters. Fishes of most singular appearance, unlike any- 

 thing else. 



a. Snout soft, not ending in a cutaneous flap ; tail not bent upward. 



CHIMERA, 28. 



28. CHIMERA Linnaeus. 



(Xt'/iatpa, Chimcera, a fabulous monster, with the head of a lion, 

 body of a goat, and tail of a serpent.) 



38. C. affinis Capello. Color plumbeous. Cold or deep water, 

 S. to Cape Cod. (Eu.) (Lat., related, to C. monstrosa.) 



