THE COTYLOSAURJA 



143 



that all the others, save perhaps the atlas, had such bones. Three 

 caudal vertebrae are preserved together, in addition to two con- 

 nected with the sacrum. They evidently bore' ribs and indicate 

 a short tail. 



The pectoral girdle I am able to restore completely with assurance. 

 The sutures between the scapula and the coracoid elements I find 

 to be as represented in the drawing, with the exception of that between 

 the scapula and the procoracoid anteriorly, of which I am in doubt, 

 because of the absence of that part of the arch on the left side with 



Fig. 4. — Pectoral girdle of Labidosaurus incisivus; one-half natural size. I, 

 interclavicle; CI, clavicle; Sc, scapula; C, coracoid; Pc, procoracoid; F, coracoid 

 foramen. 



its corroboratory evidence. There is a small but distinct, coracoid 

 foramen between the procoracoid and the scapula. There is, as 

 Case has said, no evidence of a cleithrum, nor is there any place where 

 one could have been attached. The scapular surface of the distal 

 extremity of the clavicle, of which the tip only is wanting, is striated, 

 and the scapula presents a similar surface for its attachment in the 

 position shown in the drawing. The diagrammatic position in which 

 it is necessary to figure the arch distorts somewhat the relations of 

 scapulae and clavicles. The distal extremity of the scapula was 

 evidently turned dorsad at nearly a right angle with the plane of the 



