‘Dental tusk 
a 
1884. ] Geology and Paleontology. 525 
II. Intermediate molars with four transverse crests. 
A long symphysis ; crests well separated, tubercular, with accessory lobes interrupt- 
8, ale a Sp Slik. . campester. 
MRS O18 a aol ceuan e ei M. mirificus. 
The following notes may be made on these species : 
. proavus Cope.—The two crested molars of this species are 
nearly twice as large as those of M. ouoticus, leading to the sup- 
position that some of them may belong to the “intermediate” 
series. This is confirmed by the small number of crests of the 
last superior molar of an individual from the Ticholeptus beds, 
inthe expansion of the inner base of the external half of each 
crest, which thus gives a triangular section on wearing. A femur 
indicates that this is one of the largest species of the genus. 
M. ohioticus Cuv.—Probably a descendant 6f the preceding, 
which represents it in earlier periods. 
- Serridens Cope, sp. nov.—Founded on a first or second true 
molar from Texas. It is peculiar among American species in its 
acute elevated, entire crests, with tuberculo-serrate edges. ‘It 
us resembles the M, turicensis, but differs in well-developed 
tudinal crests at the inner end of the external half of the 
“rests, which consist of two tubercles on the posterior side of a 
d on the anterior side of the next succeeding crest. 
nd posterior cingula; edge of each cross-crest 
086 SIX Or seven tubercles. Length of crown, M. .130; width, 
; eeration, 061. ngth of M. ohioticus, but narrower. 
-—This species is apparently distinct from 
but its distinction from M. humboldti has not 
i A ascertained. California. 
andit Jpodon Cope, sp. nov.—Founded on a near ly perfect left 
pe ular ramus with last molar tooth and tusk, with entire pal- 
last molar teeth and tusks. The superior tusks are 
and have an enamel band, and the inferior tusks are large 
dens and as those of the larger American form of M. angusti- 
physis ü as ‘ong as that of M. ohioticus, but narrower. Its sym- 
sis, M. i Prolonged. Length of ramus posterior t6 symphy- 
; S much larger than that of M. productus or M. 
Hazard, s Diameter of its alveolus, .068. Kansas, Frank 
M. 4 
tus Cope.—Loup Fork Beds of New Mexico. 
onSustidens Cuv. var.—Lower jaws of four individuals, two 
eae nearly complete, show that this species is found in 
