GILMORE: NOTES ON OSTEOLOGY OF BAPTANODON 300 
Wyoming, and was collected by Mr. W. H. Utterback from the marine beds of the 
Jurassic in 1902. It is now in the collection of the Carnegie Museum. 
The large size of all of the vertebrae and the long straight border of the external 
ends of the coracoids for articulation with the humeri appear to indicate a new 
species for which I propose the name Baptanodon robustus. Although the material 
at hand is insufficient for a satisfactory diagnosis of this form, yet the dimensions 
of the parts preserved, particularly the vertebree and ribs, show this to be the largest 
member of the Baptanodontide. A right coracoid, No. 1953, in the Museum of Yale 
University shows the same long straight border on the external end and may per- 
tain to this species. 
Vertebrx. — The coalesced atlas and axis are very large, and this is the first indi- 
vidual I have examined which shows the suture separating these vertebree. (See 
Fig. 12, 8.) On the lower border the atlas is 835 mm. wide antero-posteriorly, the 
axis being 830 mm. ‘The great disparity in length antero-posteriorly between the 
Fic. 12. Atlas, axis, third, fourth, fifth, and sixth cervical vertebrae of Baptanodon robustus. Type specimen, No. 
919. One half natural size. 1, Coalesced atlas and axis. 2, 3, 4, and 5, third, fourth, fifth, and sixth cervicals d., 
diapophysis ; p., parapophysis ; s., suture between the atlas and axis ; z., hypapophysis. 
lower and upper parts of the combined centra appears to be distinctive of this species. 
The hypapophyses on these vertebrae are very indistinct and no attempt has been 
made to indicate them in the drawing. (See Fig. 12.) 
On the third and fourth cervicals the parapophysis appears to be indicated by 
hardly more than a slight antero-posterior swelling on the side of the centra. In 
this respect it resembles somewhat the corresponding elements of B. marshi. The 
succeeding vertebrae have well developed parapophyses on the anterior half of the 
centra. ‘The diapophyses on all of the vertebrae preserved are very robust and con- 
fluent with the articular surfaces on the dorsal surfaces of the centra. The fourth 
