ee ae 
| 
from the Tertiary Formation. 37 
The specimens now representing this : ecies, which is one of 
sil m 
the most common fossil mammals in the earlier Tertiary of 
Western Oe peins were found by G. B Grinnell, J. W. Gris- 
wold, C. W. Betts, A. H. Ewing, J. M. Russ ell, and the writer, 
at various year near Fort Bridger, and on the White River, 
in Kastern Utah. The species is named in honor of Professor 
S. F. Baird, of the Scateheonian Institution. 
Lophiodon affinis, is nov. 
a marked = differoes sr igrinand in the contour of the crown, 
which has a deep notch in the outer posterior margin of the base, 
between the external Genes in which the transverse ridges 
terminate. In the species just described, the margin is here 
proportions. The enamel, | is s similar to that in the noine 
ing species. 
Measurements. 
Antero-posterior diameter - last upper molar. - ------ 71 lines. 
Transverse diameter of same,_---- ------------------ Ne Bi 
Antero-posterior diameter of penultimate upper molar, 8 
Transverse diameter of same,----.---------- -------- t2 
The principal specimens on which this species is established 
were found by H. D. Ziegler, in the Mauvaises Terres beds, near 
Marsh’s Fork, Wyoming 
Lophioton nanus, Sp. NOV. 
A small, col marked species, apparels a i poate 
don, is represented by a number of fossils coll 
at various localities. The arn e ee m4 ee 
specimens is a right upper jaw containing a series of four pre- 
molars, and three molars, and part of the corresponding left j 8m 
with several teeth of the same animal. The molars differ 
pecially from those of the two preceding species, in have? a 
much shallower valley between the two transverse rse ridges, and 
in having a strong basal ridge, or shelf, at the external posterior 
corner of the crown. The enamel of the whole series is very 
smooth. The species was probably about two thirds the size of 
estus. 
