GILMORE: OSTEOLOGY OF 
2. “It has a twisted shaft which is 
greatly compressed.” 
3. The distal facets are all unequal 
in size and one of them is merely rudi- 
mentary, besides they are elliptical in 
the plane of articulation.” 
4. “There is also an abnormal 
number of digits and the arm is much 
more powerful and larger than found 
in Ophthalmosaurus of equal size.” 
5. “In comparing Baptanodon with 
Ophthalmosawrus it will be well to con- 
sider that in Baptanodon the interclay- 
icle is either rudimentary or wanting.” 
6. “The absence of the intercentra 
between the second and third vertebree.”’ 
BAPTANODON (MARSH) 119 
the humerus of O. icenicus which agree 
essentially with the measurements of 
the American forms. 
2. A humerus pertaining to a spec- 
men of Q. icenicus preserved in the 
collections of the American Museum of 
Natural History, shows the same char- 
acters. 
3. The humerus of O. icenicus has 
three unequal facets on the distal end, 
though the one for the pisiform could 
hardly be considered as rudimentary. 
The facets on the distal end of the 
humerus mentioned above are elliptical 
in the plane of articulation. — Dr. 
Knight must have drawn his conclu- 
sions from a comparison of the humerus 
of B. marshi, with the humerus of 0. 
cantabrigiensis a second species described 
by Lydekker, which has three subequal 
facets, the longer axis being vertical to 
the plane of articulation. The former 
species (QO. icenicus) however is the type 
of the genus. 
4. So far as known Ophthalmosau- 
rus only has five digits and as Knight 
has observed the limb of Baptanodon 
was probably more powerful to the ex- 
tent of being broader, though the other 
proportions appear remarkably similar 
5. It is now positively known that 
Baptanodon has a well-developed inter- 
clavicle. See description, this paper, p. 
36. 
6. The absence of this bone in 
other species of Baptanodon besides B. 
marshi has yet to be demonstrated, for 
