HOLLAND: THE OSTEOLOGY OF DIPLODOCUS MARSH 261 
examined not only the specimen from No. 662, but also the specimen which 
was found with No. 84. I find that the two bones are, in spite of what Mr. Hatcher 
said, highly dissimilar, and it even appears that they may have functioned as bones 
of opposite sides of the skeleton. Their shafts are not cylindrical, but flattened 
on one side and convex on the other. They are not alike at either extremity. 
When placed side by side with the lines of their curves approximately parallel, it is 
at once seen that the broad flattened extremity of the bone recovered with skeleton 
No. 662 lies in a plane varying from that in which the corresponding portion of the 
bone found with skeleton No. 84 by an angle of at least 40°. (See Fig. 29.) If these 
d --<s2=>-- ae 
‘8 
Fic. 29. The two supposed clavicles lying side by side with their curves approximately parallel. The figure on 
the left is that of the bone recovered with skeleton No. 662, that on the right is the bone recovered with skeleton No. 
84, a-b, bifid extremities of bones; c, broad flattened ends of bones; d-e, direction assumed by flattened end of 
bone from No. 662 ; f-g, direction assumed by flattened end of bone from No. 84. 
bones are regarded as belonging to the male copulatory organ then it becomes plain 
that the position held by this organ in the two specimens must have been wholly dif- 
ferent. Accepting for sake of argument the view that the flattened end of the bone 
represents the portion of the os penis which was located in ligamentary attachments, 
proceeding from the corpus fibrosum, with its plane placed vertically after the anal- 
ogy of Lutra and other animals, then its distal extremity lay in nearly the same 
plane pointing downward, with the convex side of the shaft on the right, and the 
flattened side of the shaft on the left. Assigning to the specimen from No. 84 the 
same position, so far as its flattened, supposedly proximal end is concerned, its distal 
