20 



PERMO-CARBONIFEROUS VERTEBRATES FROM NEW MEXICO. 



obliquely downward and slightly backward and the lower, posterior, facing obliquely 

 upward and slightly forward. The inner surface of the scapula is hidden on both 

 sides in large part, rendering it impossible to describe the subscapular fossa. It is 

 impossible to trace any sutures between the bones, but both coracoids are surely 

 present. 



The inter clavicle: This bone is very little expanded at the anterior end and is 

 strongly united by deep sutures with the clavicles, resembling very closely in this 

 respect the unnamed clavicles and interclavicle from Texas (No. 4390 Am. Mus. 

 Nat. Hist. Cope Coll.) described by Case in PubHcation 145 of the Carnegie Insti- 

 tution of Washington, page 79, figure 26. The posterior portion of the inter- 

 clavicle is nearly straight, gradually becoming narrower toward the posterior end, 

 which is lost. 



Fig. 9. Diasparactus zenos Case, X 14. A, anterior view of clavicles and inter- 

 clavicle; B, upper view of right clavicle; C, outer surface of right scapula; 

 D, posterior view of right scapula. 



The clavicles: These are very strong proximally and higher than the anterior 

 end of the interclavicle. They join the sides of the interclavicle but meet behind 

 it, so that there is a median depression or fossa between the proximal ends of the 

 bones anteriorly. Seen from in front the proximal ends of the clavicles are broader 

 than high, presenting a wide flat face to the anterior edge of the scapula. A few 

 centimeters back the clavicles become suddenly flattened, so that they are very 

 thin antero-posteriorly, in the natural position of the bones, but wide vertically; 

 they continue in contact with the scapula for their full length. The distal ends 

 of the bones become gradually contracted to narrow points. 



The cleithrum: There is no trace of the cleithra attached to the scapulae on 

 either side, but there are two isolated fragments which appear to be portions of 



