CEYPTOCLEIDUS OXONIENSIS. 



179 



their anterior region, massive bones. Their form will be best understood by reference 

 to the figures. The anterior median prolongations of the coracoids towards the scapulae 

 are almost semicircular in section, the diameter of the semicircle being represented by 

 the symphysial face. This portion of the bones forms a marked projection below the 

 rest of the ventral face (PI. X. figs. 1 ^, 1 c). Behind the scapular processes the 

 concave anterior border of each bone is thin and sharp, forming the hinder boundary of 



Text-fig. 88. 



Adult shoulder-girdle of (?) Cryptocleidus oxoniensis, showing the rudimentary interclavicle : 



A, from above ; B, clavicles and interclavicle from below (outer surface). (E. 3538, about i nat. size.) 



cl., clavicle ; cor., coracoid ; gl., glenoid cavity ; i.d., interclavicle ; sc, scapula. 



the coraco-scapular foramen. External to this the bone is greatly thickened and bears 

 the facets for the scapula and the glenoid surface, these making an angle of about 135" 

 with one another : the scapular facet is triangular and is greatly roughened by pits and 

 ridges ; the glenoid facet is half an oval, the short diameter being the line of junction 



2 A 2 



