218 
COJlYPnODON. 
sandstone. The mandible is imperfect, wanting a large part oi one ramus 
and the inferior portion of the other; all the teeth are preserved excepting 
the last molar. The dentition of the cranium is perfect, excepting one 
incisor. .The cranium and mandible were found in different fragments of 
rock which had fallen from their position on one of the lower crests of the 
bad-land mass, figured in cut 15, page 91, Ann. Report U. S. Greog. Survs. 
W. of 100th M., 1875. The largest mass, which weighed perhaps two 
tons, contained the upper cranium and the femur; the other fragments were 
smaller, and lay in a ravine on the opposite side of the ridge, from the 
summit of which all the masses had fallen, and on part of which a portion 
of the sandstone bed still remains. In one block occurred the symphysis, 
with incisor and canine teeth, and parts of both rami; in another block, 
molars of both sides and a coronoid process were found in place. After 
much labor, the specimens were all removed from the matrix, and tbe sur¬ 
face cleaned for investigation. The cranium has been somewhat obliquely 
depressed. The well-worn condition of the molars shows the animal to 
have been adult, and the powerful canines render it probable that it belongs 
to the male sex. 
Viewed from the side, with the molar grinding-surface horizontal, the 
profile displays a strong elevation and prolongation backward and depression 
and abbreviation forward, so far as the cranial roof is concerned. On the 
other hand, the premaxillary region is well produced anteriorly, thus giving 
the nareal opening a direction nearly as much upward as forward. This 
production is not so great as in the existing Tapirs, but the general effect 
of the profile is Tapiroid. The superior aspect of the cranium shows a great 
width of the frontal and parietal bones, which overhang the temporal fossae, 
a strong contraction behind the canine teeth, and a rounded expansion of 
the premaxillary region. The zygomas have considerable lateral expansion, 
tbe malar bone projecting outward far be 5 ^ond the plane of the maxillary. 
Tbe latter therefore occuj)ies a sunken position between the malar bone 
and the protuberant canine alveolar wall. The posterior surface of the 
cranium is rather narrowed and elevated, the general outline being sub¬ 
quadrate, interrupted on each side below by the large mastoid processes. 
