272 THE AMERICAN NATURALIST [Vol. XLIV 



ignores the fact, that the superior surfaces of the an- 

 terior ribs and the lateral processes of the anterior dorsal 

 vertebrae unite to form a surface evidently adapted to 

 the end of providing a field over which the long dorsal 

 blade of the scapula can play. He demands for the 

 scapula a vertical position so as to give to the humerus 

 an opportunity, as he says, to move in a horizontal plane 

 backward and forward. He states that a vertical posi- 

 tion of the scapula is universal among recent reptilia, 

 which is not the case. It is true of the lacertilia, but 

 it is not true of the crocodilia. I herewith give a re- 

 production of a drawing copied from Blainville of a 

 crocodilian skeleton, and another copied from Briihl 

 (Fig. 13), both of which show that the scapula in the 



crocodile has a position in the articulated skeleton similar 

 to that which it has in the mammalia. But lest some 

 one may say that the artists were mistaken, I am able 

 through the kindness of Dr. Geo. C. Johnston, of Pitts- 

 burgh, the well-known radiographer, to exhibit a num- 

 ber of X-ray photographs showing the scapula in posi- 

 tion in the common American alligator 2 (Fig. 14). 

 These photographs show the entire accuracy of the 

 drawings of Blainville and Briihl. And I am prepared 

 to further verify the drawings by an example of an 



