Chap. IX.] 



SKULL OF ELEPHANT. 



343 



direction ; and this articular end or condyle is convex. 

 In the sheep, on the other hand, the condyle is broad 

 and flattened, and works upon a flattened or slightly 

 convex glenoid facet. 



When a large surface of attachment for the 



Fig. 144. Section of the Skull of an Indian Elephant, to show the 



Air Cavities. 

 6, Brain-case ; s, air sinuses ; n, nostril ; m, molar ; t, tusk. 



necessary muscles is required, as in the elephant, the 

 skull is not composed of thick bone throughout, .but 

 a finer bony tissue with a number of intervening air 

 cells is developed between the " tables " of the cranial 

 bones ; by these means a wider area is obtained 

 without any proportional increase in the weight of 

 skull to be supported (Fig. 144). 



