360 
ARTIODACTYLA, 
the first two premolars. This specimen exhibits the smaller dimensions of 
the true molars, the three occupying the space of the last two of J). necatiis . 
and JD. furcatus. They are rather wide, and without accessory tubercles. 
The premolars are larger than those of either of the specimens above 
described. 
Measurements. 
M. 
Length of the last four molars .. 0. 036 
Length of the last premolar .. 0. 007 
Length of the first true molar... 0. 0074 
Width of the same. 0. 006 
Depth of the ramus at the first true molar... 0. 013 
Depth of the ramus at the last true molar ... .- .... 0. 020 
Dicrocerus gemmifer, Cope. 
Plate Ixxxii, fig. 13. \ 
Mcrycodus gemmifer, Cope, Ann. Report U. S. Geol. Surv. Terrs, 1873, (1874), p. 531; 
Bulletin of do., Jan., 1874, p. 22, partim. 
A portion of the right mandible supporting the posterior molar repre¬ 
sents this species in the collection made near Santa in 1874, which is 
the part previously discovered by myself in Northeastern Colorado. With 
the latter were described some other specimens, which probably do not 
belong to the same species. This molar is the least obtained, and is more 
Deer-like than any of the others. This is seen in the short crown con¬ 
tracted at the base, and Avell defined rather long roots. There is an 
elevated basal cone between the first and second columns, and an angulate 
cingulum in front of the latter. The lake between the two median cres¬ 
cents continues inward and backward to the inner face of the crown as 
a fissure, which prevents the fusion of the inner and fifth lobes of the 
crown, except on prolonged attrition. A trace of the same is seen in the 
more fully-worn type-specimen from Colorado. Enamel obsoletely rugose. 
Measurements. 
M. 
Long diameter of crovTU . 0.012 
Short diameter of crown. . . 0.0055 
As already remarked, I suspect that this species will be found to belong 
to a genus distinct from Dicrocerus. 
