V 
THE CHIMAROIDS 
CHIMZROIDs are shark-like in their general characters, 
but cannot be looked upon as in any strict sense closely 
_ associated with the Elasmobranchs. They constitute the 
second of the more important groups of fishes. Their 
typical representative is the Chimezera, spook-fish, or sea- 
cat (Fig. 119). 
Structural Characters 
The typical structures of Chimera are shown in the dis- 
section given in Fig. 104. Its thick, round, and blunted 
head tapers away gradually to the tip of a diphycercal tail, 
C. The body surface is generally smooth. The paired fins 
are somewhat shark-like, but their dermal margins have be- 
come greatly enlarged, tapering distally to an acute point ; 
the foremost dorsal fin provided with an anterior spine folds 
like a fan and may be depressed into a sheath, SH, in the 
__ body wall; this fin and the hinder ones are largely dermal, 
D’, basal and radial supports existing only at B’, RX’. The 
"gill arches, BA, may be seen to be closely drawn together; 
_ their outer openings are now reduced to the slit-like aper- 
_ ture beneath the dermal flap, OP. Teeth exist in the 
_ form of dental plates, closely fused with the jaws; as 
_ shown in the figure, D, three of these occur in each side, 
_ asingle one on the mandible, an anterior and posterior on 
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