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V'-ti' 



а character of the Permian humerî*Tre5r^nder conside- 

 ration. They are also furnished with a radial supracondy- 

 loid foramen (ectepicondylar of Owen) found in some 

 lacertians and chelonians. 



Fig. 1. is a portion of a left humerus. The proximal 

 end and the external or radial condyle are deficient. 

 The interior substance is almost entirely converted into 

 sandstone and the size of the medullary cavity is thereby 

 rendered undefmable. The osseous structure is dense 

 and hard. 



unlike most mammalian humeri, which have tumid 

 ends, the distal end of this specimen is broadly expan- 

 ded, the constricted shaft alone being rounded. The 

 olecranal depression is flatter and shallower than in 

 mammals. These considerations indicate its reptilian na- 

 ture. The disto-radial crest is traversed by a canal ec 

 opposite the ulnar perforation en. The crest being bro- 

 ken at this point it would be imprudent to positively 

 predicate the existence of a perfect bridge or merely of 

 a hook. From its appearance I incline to the belief that 

 the canal was completely arched over. The entepicondy- 

 lar foramen ем is situate fully 3 inches above the arti- 

 culation and assumes the form of a broad canal direc- 

 ted downwands and forwards, showing traces at each 

 side of having been crossed by an osseous bridge. The 

 form of this canal closely resembles that in Cynodraco 

 major *). 



*) Quart. Journ. Geolog. Society, May, 1876, pi. XL 



