48 



MAEINE EEPTILES OF THE OXEOED CLAT. 



border bent downwards. The thickened portion terminates in a broad cartilage- 

 covered surface, the widest posterior end of which forms the front of the glenoid 

 cavity [gl.f-), while in front of this is the articular surface (cor.f.) for union with the 

 coracoid. In front of this again the free lower border of the bone may either 

 have been bordered with cartilage, or in old individuals may become smooth and 

 rounded, forming, according to Professor Seeley's interpretation, the outer edge of a 

 fenestra, the other sides of which are constituted by the notch of the coracoid and 

 a precoracoidal cartilage. In front of this, as far as the antero-internal angle, the 

 inner border is again thickened and deeply grooved and pitted for union with the 



Text-fig. 33. 



S.SC.b. 



a.cL 



a. a. 



_J9'f%^ 



Scapula of Opliihalmosaurvs : A, from above ; B, proximal eud; C, proximal end of scapula of the 

 type specimen. (A & B, E. 2137 ; C, E. 2133 : about | nat. size.) 



a.a., acromial angle; cl.f., facet for clavicle ; cor.f., facet for union with coracoid ; 

 gl.f., glenoid surface ; s.scl., suprascapular border. 



cartilage which, according to the views just referred to, was continuous with that 

 capping the anterior border of the inner side of the coracoid and was homologous 

 with a precoracoid element. The upper (visceral) face of the expanded portion of the 

 scapula is flat or slightly concaA'e and is deflected sharply downwards in fi-ont, as 

 mentioned above ; the degree of deflection of this anterior border differs very 

 considerably in different specimens, but in no case is a broad flat anterior surface 

 formed for union with the clavicle, such as is figured by Gilmore (op. cit.) in the 

 shoulder-girdle of JBaptanodooi ; there may, however, be an extension of the rough 

 clavicular surface, best marked on the anterior edge of the blade of the scapula, so 



