SKELETON. 



603 



just in front of the basioccipital, is covered over by a 

 membrane bone — the basitemporal. In -front of this is a 

 sharp " basisphenoid rostrum " or parasphenoid, also a mem- 

 brane bone. Articulating with the quadrate and with the 



rostrum are the pterygoids, in front of these lie the palatines. 

 The vomer is vestigial. The bony front of the palate is 

 formed from inward extensions of the premaxillae and 

 maxillae. The interorbital septum is formed chiefly from 

 the mesethmoid, but also from the presphenoid. From the 



