454 
EXTINCT BOVID^, CANID^E AND FELID^ 
bone with teeth from Indiana. On comparison with Leidj’s type which is in the 
museum of the Academy of Natural Sciences of Philadelphia, I find the following 
differences : 
The second premolar is distinctly longer, and the external cingulum is much 
weaker. In C. indianensis this cingulum surrounds the crowm posteriorly, and here 
in the present species the trace of it is especially weak. The internal root of the sec- 
torial (first premolar) is inserted opposite to a point wdiich marks the po.sterior third 
of the tooth in front of it, while in C. indianensis this alveolus is opposite that of 
its paracone. In the first true molar the protocone is more conic than in the Texas 
dog, having a round section, while in the latter it is lenticular. The external cin- 
gulum in the Texas dog is weaker. 
The specimen from the Staked Plain belongs to an older dog than Dr. Leidy’s 
type, which partly accounts for the weakness of the external cingula. I am in- 
clined at present to regard it as an individual of the same species, suspecting that 
new material will confirm the reference. Leidv has referred a lower jaw from 
California to C. 'indianensis. This species and Dinobastis serus represent the larirest 
Canid® and Felidm of the Ecpius bed respectively. 
American Naturalist, 1893, p. 896. 
Generic ^ character far as preserved, the parts agree wdtli those of the genus 
Smilodon, with one exception. This is that the superior sectorial tooth iiossesses 
no internal root, not even a rudiment. The protocone is wan ting in Smdodon, but 
its comspondmg root is present, but in this form the root also has disappeared, so 
that it may be regarded as presenting its last stage of specialization in the cats, a 
circumstance which is appropriate to its late appearance in time. 
DINOBA.STIS SERUS Cope, loc. dt. Plate XXI, Figs. 1 - 13 . 
The known remain of tills species include parts of three metacarpals three 
five mcsots two superior canines, .and two molars, one of them tiie snm.rior sec 
orfcXoTtrfrnXotX"^^^^^^^^ Macained fun size, hut the opiph.vsis 
lion {Uncia leo), of the same ao-e • m H +1 ’ ^ are ecpial to those of a 
those d Smilodon LeidV and f^tl 
Lund, of South America. ‘ smaller than those of A. neogcrus 
Specific characters . — The mulno +^,^.+1 
crowins, a little more convex on the external compressed 
edges are finely serrate Then + n i internal face. The cutting 
,f^^.«in thatiUurnsinwmrdtowLrthebaS of Smilodon neo- 
S. neogceus this edge is not incurved rp. ^ presenting inward. In 
ior basal lobe and a laidimeiit of n 1 
tain the importance of a lobe as itToL ^ ^'iterior base. The latter does not at- 
terior to the paracone forms ’about one-Crtl/oft/’ 
uitli of the longitudinal extent of the 
