EGGS, HATCHING, AND CARE OF YOUNG 141 



that tliey breathe easily when near the surface with- 

 out thrusting the head far up. In one of the croco- 



FiG. 63. — Gfivial (Gavicdis gangetiea) . 



dilians — the Gavial (Fig. 63) — the male has a great 

 warty bunch on the snout through which the nostrils 

 open. 



Eggs, Hatching, and Cake of Young 



We have spoken of the eggs of reptiles as being 

 large and free from each other — like those of birds. 

 Those of the crocodilians and all tortoise-forms, ex- 

 cept the paddle-feet kinds, have limy hard shells, but 

 in all others a tough membrane only covers them. 

 They consist of a yolk and " white '' as in hen eggs, 

 and in no case are they fertilized (or made so they 

 will hatch) after they have been laid, as is the case 



