0 [Sept. 19, 
MIAcIS PARVIVORUS. Cope. Gen. et sp. nov. 
tions of three molars, the penultimate being perfect. As in Canida, the 
molars diminish in size posteriorly, the last being single-rooted, the 
penultimate being two-rooted. The structure of that tooth is approx- 
imately that of Stypolophus, ¢. e., with three trihedral cusps in front and 
a heel behind, but the cusps are of equal height, and their point of uniom 
not raised above the surface of the heel. This is a valley bounded by a 
sharp margin which is incurved to the outer cusp, leaving a vertical 
groove on the outer side, as in Stypolophus sp. This genus further 
differs from that one in the single-rooted small tubercular posterior molar, 
which is wanting in that one. The ante-penultimate molar is much 
larger than the penultimate. The crown of the latter is laterally ex- 
panded, and bears a cingulum at the base antero-externally.. Enamel 
i Established on a portion of the right ramus mandibuli, containing por- 
| 
| 
smooth. 
M. 
Depth ramus at penultimate molar....... Cars iaaeile 0,0080 
Length crown of ies Oo epee scale Evie ss | -0040 
Elevation ie ny Bila. ota ta ee ie Mera ae 0025 
Width ce ee een OR Ce a Be 0083 
Found on Black’s Fork of Green River. <An ally of Stypolophus and 
Triacodon. 
TOMITHERIUM ROSTRATUM. Cope. Gen. et sp. nov. 
229 
Allied to Notharetus, Leidy. Dental formula 777%, in an uninter- 
rupted series. Last molars with five tubercles, others with four; all 
low and slightly alternating, the outer wearing into crescents. Canines 
quite small. Incisors very prominent, the median pair with transverse 
cutting edges. Symphysis codssified, projecting in front. 
I base the distinction between this genus and Wotharctus on the small 
canine, and the sub-horizontal position of the incisors; believing that 
when other portions of the skeleton are studied, other differences will 
appear. This, I have the opportunity of doing with material now in my 
hands, 
The adjacent horns of the two outer crescents unite with the anterior 
outer tubercle ; the posterior outer is insignificant. There is a projection 
but no tubercle in front of the outer anterior tubercle. The first and 
second premolars have but one root, the base of the second being about 
the size of the base of the canine. The latter are cylindric at base. The 
incisors form a parabolic outline, and have entire edges, the middle pair 
transverse ones. Enamel generally smooth, premolars somewhat striate ; 
an indistinct inner cingulum. 
M. 
Length of entire dental series (straight)............... 0.044 
« AY MODMY SIS MANGO UOUIE. i. 6k a, cs eee me a ey 020 
Depth ramus at second molar...... ii nas Wee sge dees ULO 
Length crown of — ‘ OO are arity eye oh eenrrl i, 
