THE SKULL. 



27 



The maxillary bones contain the sockets of all the npper teeth. The 

 socket for the canine is a large and deep cavity, elongate -oval in section, 

 and extending u})ward and backward to the i)Osterior part of the base of 

 the large maxillary pnjtuberance. The onter surface of the maxillary 





Figure 28. — Skull of Tinocerus inyens, Marsh ; seen from Ijelow. 

 Figure 29. — Skull of Tinoceras jmgnax. Marsh; same rieu-. 



a. anterior palatine foramen; 6. palato-masillary foramen; c. antoiliital foramen ; (?. prsterior palatine 



foramen; e. posterior nares; /. forauiea magnum; /'. occipitiil for.imen ; ij. st_vlo-niastoitl foramen; 



h. foramen lacenim ; i. vascular foramen in basisphenoid : j jiostcrior opening of alisplienoid cat/al; 



k. anterior opening of alis[,henoid canal ; 1. ontic foramen. 



Tolh fii'ures are one-(ighth natural size. 



