512 



ZOOLOGY 



SECT. 



only gives rise to a tube for the external auditory meatus, but also 

 forms the hidla tympani, a dilated bony process containing a cavity. 



The occijntal region presents two condyles for the articulation of 

 the atlas. 



The mandible consists in the adult of one bone, the equivalent 



of the dcnUiry of Sauropsida, on each side — the two rami, as they 

 are called, beingju most Mammals closely united at the symphysis. 

 The mandible articulates with an articular surface formed for it by 

 the sqxiamosal bone, below the posterior root of the zygomatic 

 arch. 



