ELASMOBRANCHII — HOLOCEPPIALI 



471 



transverse ridges, and no doubt belonged to a Japanese Chimaera} 

 In neither egg-case was there any trace of tendrils. The eggs 

 probably lie on the sea-bottom, or, when the cases have styliform 

 prolongations, it is possible that they are implanted in the ooze. 

 Callorhynchus (Fig. 269) is distinguished by a singular pro- 

 longation of the rostrum, which terminates in a downwardly- 

 directed cutaneous flap, evidently from its abundant nerve- 

 supply an important tactile organ. 

 A frontal clasper is present in 

 the male. The prolonged caudal 

 axis is up-tilted, and the tail is 

 more distinctly heterocercal than 

 in Chimaera. The only species, G. 

 antarcticus, is confined to the Ant- 

 arctic basin and the South Pacific. 

 The egg -cases of Callorhynchus 

 differ considerably from those of 

 Chimaera, and so large are they 

 that one may measure 25 cm. in 

 length, or nearly as long as the 

 abdominal cavity of the Fish. Each 

 case is ovoid in shape, surrounded 

 by a wide flat margin which is 

 covered on one side with yellow 

 hair-like fibres, thus giving to the 

 case a protective resemblance to a 



mass of seaweed (Fig. 270). In Fig. 270.— Egg-case of Callorhynchus 



the central part of the case there anUrcticusMiH open to show the 



^ _ _ embryo and its lobed yolk - sac 



is a pear-shaped cavity in which (y.s) ; s, dorsal spine. (Cambridge 



the egg or the embryo is contained. useum.) 



From one end of this cavity a passage, guarded by a valve, leads 



to the exterior, and provides for the escape of the young. While 



in the egg-case the nearly ripe embryo has long external gills, 



and its body is nearly sessile on a large and singularly lobed 



yolk-sac. 



The third genus, Harriotta, (Fig. 271),^ is remarkable for its 



^ See also an account of the egg-case of a Chimaeroid dredged from a depth of 

 516 fathoms in the Bay of Bengal (Wood-Mason and Alcock, Ann. Mag. Nat. 

 Hist. (6) viii. 1891, p. 21). 



^ Goods and Bean, op. cit. p. 32. 



