GILMORE: OSTEOLOGY OF BAPTANODON (MARSH) 115 
species. Having made a personal examination of the extremity mentioned above 
I find the figure to be a faithful reproduction of the limb, which clearly shows the 
upper limb bone as having three facets, distally as originally described. However 
Dr. Knight has observed that the distal extremities of the femora examined by him 
Fig. 24. (a) dorsal view of humerus of Baptanodon marshi from type specimen. One half natural size. h, hu- 
merus ; p, articular surface opposite the pisiform ; r, articular surface for radius; ¢, trochanter; w, articular surface 
for ulna. (b) View of distal articular end of the same. One half natural size. 
all have two facets only. This isimportant and raises the question as to the correct 
determination of the paddle designated as the left pelvic limb of B. discws by Marsh. 
This would be an important character for distinguishing the genus Baptanodon 
from the closely allied genus Ophthalmosawrus, which is accredited with three facets 
on the distal end of the femur. A photograph before me of askeleton of Ophthal- 
te e) CO) @©000., 1 
a — Y) @BOO0000,, 
Oe Le) @O@Oo OO, 
@@ O00000¢,, 
9 (O09 Ooo¥ 
7) @ QO? 
Fic. 25. Left hind (?) paddle of Baptanodon discus (No. 1955) seen from below. One eighth natural size. f, 
femur ; ¢, tibia; fi, fibula; p, pisiform or epipodial supernumerary ; /, first digit ; v, fifth digit. 
mosaurus shows the pelvic limb as being much smaller than the pectoral and this 
would strengthen somewhat the idea that Professor Marsh was mistaken in his inter- 
pretation of this extremity. 
So faras I am able to learn there has not been a hind limb of Baptanodon found 
intact and at this time it will be impossible to definitely determine the correct solu- 
