OPHTHALMOSAUEUS. 



47 



elongate coracoid, such as occurs in the more primitive members of the group — e.g. 

 in Shastasaurus os7nonti, from the Trias of Northern California, the coracoid of which 

 is figured by Merriam *. The present condition of this notch is due to the great 

 expansion of the bone generally, and there seems to be no sufficient evidence for the 

 view that it formed the posterior border of a foramen closed in front by a precoracoid 



Text-fig. 32. 



Left coracoid of Ophthiilmosaurus : A, outer end ; B, upper surface ; C, inner (syinphysial) end. 



(E. 2137, J nat. size.) 



a.n., anterior notch ; eor.f., surface for union with opposite coracoid ; gl.f., glenoid facet ; 

 j).h., posterior border ; scap.f., facet for scapula. 



cartilage ; certainly, even in the earliest forms there is no ti^ace of any ossified pre- 

 coracoid. No doubt the short anterior prolongation of the coracoid internal to the 

 notch was capped with cartilage, as also was the inner process of the scapula, but there 

 is no evidence that these two cartilages ever joined to enclose a fenestra. 



The scapula (text-fig. 33) is greatly expanded towards its lower end, which is also 

 greatly thickened posteriorly, while anteriorly it is thinner, and towards its anterior 



* Bull. Dept. Geol. Univ. California, vol. iii. (1902-4) pi. x. See also coracoid of Shastasatm(s 

 alexaiidrce, figured ojj. cit. pi. xii.. 



