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1924]
Loomis, Miocene Oreodonts in the American Museum
The species is very similar to M. elegans, but the upper dentition,
so far as known, is so largely deciduous that comparisons can not be made
on this character. The lower dentitions, however, can be compared.
While the length over all of the two premolar series is nearly the same, in
M. paniensis the first lower premolar is considerably smaller; premolar 2
is considerably larger; premolar 3 somewhat larger, and premolar 4 of
about the same size. The whole dentition of M. paniensis is lighter,
both the premolars and the molars being narrower.
A.M.14057
A.M.49046
Fig. 24. Fig. 25.
Fig. 24. Merychyus paniensis, front foot from No. 9046. One-half natural
size. Fig. 25. Ticholeptus hypsodus, lower jaw from the type. One-half natural size.
TICHOLZPTUS
This genus was established to include those oreodonts with limbs of
intermediate length and with skulls of a mesocephalic or brachycephalic
type, on which the supra-orbital crest is high, the exoccipital region
broad, the bullae large, and the antorbital vacuity large. The teeth are
shortened from front to back, and the lower fourth premolar is distinguished
by having the anterior crest bifurcated at the front end. It
ranges from the Lower Harrison be(ds up into the Snake Cr;eek.
Ticholeptus hypsodus, new species
This is one of the oreodonts from the Snake Creek beds, twentythree
miles south of Agate, Nebraska. I have taken No. 14057, a lower
jaw, as the type. The pattern of the teeth is that typical of Ticholeptus,
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