VERTEBRATES FROM PERMIAN OF TEXAS 



397 



terior edges are raised so that the cavity is almost a semicircle; 

 in the reptiles the cavity is shallower and more widely open. 

 The articular face of the cotylus differs in the two. In Eryops it 

 is about equal in width at the two ends, but is abruptly wider a 

 little anterior to the middle point ; in the reptiles the two ends 



are the wider and the 



middle portion is of equal 

 width. 



A second scapula, No. 

 1 86 of the collection, dif- 

 fers from any heretofore 

 seen by me in its short- 

 ness and relatively great 

 width. As it has a free 

 coracoid, no trace of an 

 episcapula, and a very 

 narrow face for cartilage 

 on the anterior edge of 

 the epicoracoid, it is re- 

 garded as reptilian, and its robust character shows that it 

 belongs to some genus of the Diadectidae. It so probably belongs 

 to a species already named that I have given it no new name 

 here, leaving its identification to future discoveries. Fig. 3 gives 

 the best idea of its general form. Notable, in comparison with 

 the other scapula, is the great width of the anterior edge and the 

 great width of the median portion, which is as wide as any part 

 of the anterior edge. At its posterior two-thirds the bone nar- 

 rows rapidly and terminates in a thin blade, which shows the 

 marks of cartilaginous attachment on its distal and upper edges. 

 There are two foramina in the bone in much the same position as- 

 in Eryops, and both open into a large pit on the inner surface of 

 the bone. The anterior foramen opens on the outer face in a 

 deep pit located just anterior to the prominent edge of the upper 

 portion of the humeral cotylus, instead of somewhat farther out 

 upon the epicoracoid, as in Eryops. The scapular and epicora- 

 coidal portions meet at the suture in an angle of about 80°, as 

 shown in the figure by the lighting of the photograph. Just 



Fig. 3." — Scapula, coracoid, and epicoracoid of 

 a diadected reptile. Right side. 



