90 



Annals of the Carnegie Museum. 



Between the origin of the transverse process and the ventral keel 

 there is located on the centrum a deep pit, which is apparently more 

 emphasized than in Poebrotherinm. As in the latter, the vertebrarterial 

 canal extends throughout the entire length of the side of the neural 

 canal, and is plainly visible from the side, entirely unlike what is ob- 

 served in the tylopods, and more like the condition found in the 

 Bovidcc. The sixth and seventh cervicals are so badly mutilated that 

 an accurate description of them is not possible. 



No dorsals are present, and there are only four posterior lumbars 

 represented. The two vertebrae anterior to 

 the last (the fifth and sixth) have the cen- 

 tra quite long, with prominent ventral keels, 

 and also well developed neural spines. The 

 last lumbar, as usual, has a shorter and 

 more depressed centrum. So far as compari- 

 son is possible, these parts agree well with 

 the description and illustration by Wort- 

 man {I.e., p. 107). 



This individual also presents for the first 

 time the complete metacarpals III and IV, 

 the proximal end only of Mc. II is preserved, 

 while Mc. V is lost. As Professor Scott has 

 shown (I.e., p. 36) the metacarpals are rela- 

 tively short and otherwise differ from those 

 in Poebrotherinm. An illustration is here- 

 with gi\en of the metacarpals and the 

 metatarsals (See Fig. 14). 



Both hind feet are represented and the 

 most curious feature is the characteristic 

 bovine coossification of the cuboid and the 

 navicular in the tarsus of both feet, which 

 is hard to believe to be anything but purely 

 pathological, especially since the entocunei- 

 form of the right tarsus also has a tendency 

 to become coossified with the cuboid.^" In 

 another specimen (No. 2977) of slightly 

 larger size and also fully adult, or old, both hind feet are preserved, 



Fig. 14. Proiylopus pcler- 

 soni. Carnegie Museum 

 No. 2948. X i/i. I. Left 

 cubonavicular, dorsal face. 

 2. Left Mc. Ill and IV, dor- 

 sal face. 3. Left Mt. III. 

 and IV. dorsal face. 



^^ In certain Antelopes as Calablepas gnu, the entocuneiform appears to be partly 

 coossified with the cubonavicular bone. 



