350 
ARTIODACTYLA. 
Some of the specimens of this genus display the accessory tubercles, 
or rudimental columns between the inner lobes of the inferior true molars 
characteristic of the Cervi. I find them in very different degrees of devel¬ 
opment; while they are prominent in D. gemmifer, Cope, there is a rudi¬ 
ment in the first true molar of a specimen of D. necatus. Under the circum¬ 
stances, the species may be distinguished by the mandibular rami and den¬ 
tition, as follows; 
I. True molars without or with one rudimental accessory basal 
column. Dicrocerus. 
Larger, length of preraolar series 0™.020; teeth compressed; 
ramus very slender at the diastema. I), furcatus. 
Size similar; teeth less compressed; ramus stouter at dias¬ 
tema . D. necatus. 
Size smaller; premolar series 0“.016. D. tehuanus. 
II. Time molars with more or less developed basal columns. Blastomeryx. 
Smaller; last molar 0“.013, less prismatic; basal columns w’ell 
developed.. D. gemmifer. 
It is quite possible that the species last named may represent a genus 
distinct from those preceding it, but the last molar tooth is the only part of 
the dentition which is known. In that case, the name Blastomeryx may be 
applied to it. I obtained it first* in the Loup Fork beds of Eastern Colo¬ 
rado; a specimen from the Santa Fd marls resembles it closely. The 
largest two species have not left many teeth. 
Dicrocerus furcatus, Leidy. 
Plates Ixxx ; Ixxxi, fig. 1; Ixxxii, fig. 1. 
Conoryx furcatus, Leidy, Jour. Acad. Phila., vii, 1869, p. 173; PI. xxviii, fig. 8. 
Cosoryx ramosus, pars, Cope, Proc. Acad. Phila., 1874, p. 148; Ann. Kept. Chief of 
Engineers, 1874, ii, j). 604. 
Dicrocerus furcatus, Cope, Proc. Acad. Phila., 1875, p. 257. 
The horns of eleven individuals referable to this species were obtained 
by the expedition of 1874, and one of these is accompanied by a tooth 
which enables me to identify the separate lower jaws of two individuals as 
belonging to the same. The horns present common characters, but differ 
somewhat in size, the largest specimens considerably exceeding Dr. Leidy’s 
type in this respect. 
This species is about the size of the B. necatus, and differs from it in 
*See Ann. Kept. D. S. Geol. Surv. Terrs., 1873, p. 531. 
