T^NIODONTA. 
167 
enamel face. The triturating surface is nearly round, excepting a small 
entering loop of enamel on the inner side. It is worn obliquely, an angle 
of the circumference projecting beyond the rest. The enamel is marked by 
obsolete longitudinal riblets. The root contracts downward. 
Measurements. 
Diameter of the enameled part of the incisor i ■ 
(longitudinal... 
Diameter of the base of the crown of the molar 1 transverse . 
(longitudinal. 
Length of the crown of the molar on curve... 
M. 
0. 019 
0. 015 
0. 015 
0. 015 
0. 041 
The molar tooth of this specimen differs from the one described as 
belonging to the C. arcanmnus. It is more prismatic and curved, and the 
enamel is more unequally distributed on its sides. The crown is more con¬ 
tracted. These differences are important, and are not dependent on attri¬ 
tion, since the short-crowned molar, that of (7. arfiamoenus., is unworn, and 
the long-crowned one of C. simplex is considerably so. 
Another individual is represented by more abundant remains. It 
includes inferior and superior incisors, a molar, and portions of the cranium 
and limbs, especially humerus, ulna, radius, magnum, unguis, scapula, etc. 
The inferior incisors jnesent the features already ascribed to the spe¬ 
cies. The superior incisor is a remarkable tooth, and has associated with it 
a smaller curved incisor, which appears to me to belong to the same jaw, 
although this point is uncertain. The large tooth is equal in antero-posterior 
diameter at the base and at the masticating face, and is gently curved. It is 
flattened in an antero-posterior plane, which is slightly twisted. The enamel 
faces are convex and oblique in reference to the cross-section, the supero- 
anterior one especially declining to one side. This side is'excavated into 
a shallow channel from one end to the other. The opposite side of the 
tootli is nearly plane or slightly convex at the masticatory face, and a little 
more concave near the root. The triturating surface is truncate. The 
enamel is smooth, excepting minute transverse lines of growth. The small 
incisor differs from the large one in having, like the inferior, only one face, 
the convex, protected by enamel, which is a narrow strip. The shaft is 
curved, and is oval in section. The masticating surface is transverse. The 
