OSTEOLOGY OF AMERICAN PERMIAN VERTEBRATES 383 



I find any trace of a supracoracoid foramen; a notch below the 

 lower preglenoid process may represent the vacuity for the passage 

 of the artery. An opening corresponding to the supraglenoid 

 foramen seems to be present just above the supraglenoid articular 

 surface. Apparently the suture distinguishing the coracoid in 

 front is seen in a division across the bone, which I have indicated 

 by a dotted line; but I cannot find the least trace of an anterior 

 suture. 



Doubtless the scapula proper must include all that part above 

 the upper facet; possibly the lower preglenoid process is on the 

 anterior coracoid, if there be such a bone in this scapula. At the 

 upper end the scapula is rather narrow, with a thin front border, 

 and a thickened posterior border. If the two coracoids met along 

 the middle line, the blade of the scapula must have projected 

 strongly forward. But that is improbable. Probably the two 

 sides approximated each other only at the posterior end, leaving 

 a large V-shaped interval between the anterior borders, partially 

 filled out by the clavicles and interclavicle. 



Humerus. — Three complete humeri are preserved free (Fig. 2). 

 Two other complete ones, of a somewhat smaller size, are preserved 

 in the matrix, associated with skeletal bones ; and there are various 

 other parts of juvenile humeri that were found in the clay matrix, 

 portions of which have been lost. The articular head in the best- 

 preserved specimen (Fig. 2, £) is oval in shape, and is not widely 

 separated from the lateral process, which is much nearer the head 

 than is usual in Permian reptiles. The bicipital fossa is rather 

 shallow. The distal extremity is thin and flat, and is only moder- 

 ately expanded on the ulnar side. The entepicondylar foramen is 

 small, and is bridged over by a very delicate bar of bone, so delicate 

 that it has been lost in all our specimens. Indeed, so thin is the 

 broken edge left above the foramen that for a time I was in doubt 

 as to whether it was not merely a notch. I am now convinced that 

 the foramen was closed in; nevertheless it seems to be obsolescent. 

 On the radial side there is an ectepicondylar foramen, quite as in 

 modem lizards, formed by a slight bridge over the end of the ectepi- 

 condylar groove in the adult humerus, but wholly wanting in the 

 juvenile specimens. The capitellum is well formed, as is also the 



