24 HOLOCEPHALLI. 
SUBCLASS HOLOCEPHALI. 
This group, defined on page 13, is equivalent to the” 
OrvER 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 vertebre 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. (6dos, solid; xepadn, head.) 
Famity XIX. CHIMAjRIDA. 
Forehead of males with a movable cartilaginous hook, turned 
forward and armed with prickles at tip. Oviparous, the egg- 
ceases 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. CHIMZ]RA Linneus. 
(Xivatpa, Chimera, 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.) 
