XTTI 



PHYLUM CHORDATA 



183 



mental characteristics with the Elasrnobranchii, and is sometimes 

 included in that sub-class. Q the recent genera, Chimaera, the 

 so-called "King of the Herrings" (Fig. 858, A), is found on the 

 coasts of Europe, Japan, and Australia, the west coast of North 

 America, and at the Cape of Good Hope ; Callorhynchus (B) is 

 tolerably abundant in the South Temperate seas ; Harriotta is 

 a deep-sea form. 



External Characters. The general form of the body is 

 Shark-like, but the large, compressed head and small mouth are 



FIG. 858. A, Chimaera monstrosa ; B, Callorhynchus antarcticus. a. cl. anterior 

 clasper ; a. cl.' pouch for its reception ; br. ap. branchial aperture ; c.f. caudal fin ; c.f.' its 

 whip-like prolongation ; d. f. 1, d.f. 2, dorsal fins ;fr. cl. frontal clasper ; /./., I. f.' labial 

 folds ; 1. I. lateral line ; na. ap. nasal aperture ; op. operculum ; pet. f. pectoral fin ; ptg. 

 pterygopodia ; pv.f. pelvic fin ; t. teeth ; tc. tactile flap ; v.f. ventral fin. (A after Cuvier.) 



strikingly different from the depressed, shovel-shaped head and 

 wide mouth of most Selachians. The mouth is bounded by lip-like 

 folds, two of which (B, l.f., l.f.'), placed laterally and supported by 

 labial cartilages, resemble the folds in which the premaxillae and 

 maxillae of many Bony Fishes are enclosed : a third fold, external 

 to and concentric with the mandible, is also supported by labial 

 cartilages and has the appearance of a second or external lower jaw. 

 In Chimsera the snout is blunt, in Harriotta long and pointed : in 

 Callorhynchus it is produced into a rostrum, from the end of which 



