the quadrate, and posteriorly presents two sulci, [71 and 

 72, fig. 43] the outer of these has been mentioned above, 

 the inner is much smaller, it gives attachment to the inner 



alls) [3]. The apex of the process articulates with the 

 opisthotic (fades opisthotic) [10]. 



The Basioccipital (Os occiptalc basihire) [fig. 22] is 

 composed of three short stout rami attached to a quadrate 

 body. A triangular area on the upper surface of the body 

 shares in forming the floor of the cranial cavity (facie* 

 cerebmlis) [1]. The anterior angles of the triangular cere- 

 bral surface are truncated by a bevelling of the bone where 

 it shares in bounding the auditory capsule (fades otica) [2]. 

 Between these there is an oval tubercle [3] which gives 

 attachment to the bifid ligament of the medulla. Lateral to 

 and behind cerebral and otic surfaces the upper surface of 

 the body is flush with the sloping upper surfaces of the 

 paroccipital [4] and condylar [5] rami, the whole area thus 

 formed on either side articulates with the exoccipital [C]. 

 Anteriorly the body articulates by synchondrosis with, the 

 basisphenoid. The paroccipital rami spring from the body 

 on either side ventrally. Anteriorly each presents a ptery- 

 goid surface for articulation with the basitympanic portion 

 of that bone, and beneath these is an arcuate area for 

 articulation with the upper surface of the basipterygoid 

 processes of the basisphenoid. The condylar facet [7] 

 occupies the end and a small area on upper and lower 

 surfaces of the condylar ramus. On the posterior aspect 

 of each paroccipital ramus is a smooth surface which is 

 continued a little way along the lateral surface of the 

 condylar ramus, this arcuate surface [8] forms the lower 

 half of the paroccipital fossa [61, fig. 43]. 



The Exoccipital (Os- ocdpitale laterule) [Figs. 23, 24, 

 and 25] consists of a stout body [1] bearing condylar [2] 



