24 HOLOCEPHALI. 



Subclass HOLOCEPHALI. 



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



Order VI. HOLOCEPHALI. 



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. No spiracles. Jaws with- 

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

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

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

 highly developed mucous system. Dorsals each with a strong 

 spine. One family. (6Aos, solid ; Kfcfrakfj, head.) 



Family XIX. CHIM^ERID^E. 



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. 



(Xlfiaipa, 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.) 



