UPON HTPTCRODAPEDOX GOEDOXI. 683 



Rhynchosaurus, and Sphenodon, illustrating the variations in their 

 and form. 



Fig. 4. — Skull of Hyperodapedon, under view. 



(Plate XXYI. fig. 4). The anterior and superior angle of each is 

 prolonged into a " rostral " process (r.m), which passes upwards, out- 

 wards, and forwards. The two thus leave a wide Y-shaped interval, 



3a2 



