PANTODONTA. 
187 
PANTODONTA. 
CORYPHODON, Owen. 
CorypJiodon, Owen, History British Fossil Mammals, 1846, p. 299, figs. 103, 104.—Bronn, 
Lethsea Geognostica, 1856, p. 842.—Hebert, Annales des Sciences Natnrelles, 
1856, p. 87, plates. 
Bathmodon, Cope, Proceed. Amer. Philos. Soc. 1872, Feb. 16, 1872; Ann. Eept. H. S. 
Geol. Survs. Terrs. 1872, p. 586 (1873); System. Cat. Vert. Eocene New Mex¬ 
ico, U. S. Geog. Survs. W. of 100th M., 1875, p. 24. 
The remains of this genus have been preserved in greater abundance 
in the Wasatch beds of New Mexico than in any other known region of 
the world, so that a good opportunity is offered for an elucidation of the 
structure of its skeleton. The bones obtained include all parts of the skel¬ 
eton and skull. 
Cranium and dentition. —The skull is moderately elongate, the elongation 
being behind the orbits, since the muzzle is rather short. The free part of the 
nasal bones is short and narrow, and the bones are not co-ossified. The 
premaxillary region is expanded, so as to extend beyond the nares. The 
latter are thus directed obliquely upward. The face is greatly contracted 
immediately behind the canine teeth. The superciliary borders are not prom¬ 
inent, but immediately behind the orbits the superior margin of the tem¬ 
poral fossa expands and becomes an overhanging roof to its posterior border, 
which is beyond the vertical plane of the occipital condyles. The borders 
of opposite sides unite in a deep notch on the middle line above, and over¬ 
hang the concave supraoccipital region. The zygomatic arch is considera¬ 
bly expanded laterally. The foramen infraorhitale is rather large, and issues 
not far in front of the orbit, and in the same horizontal line. The lachrymal 
canal passes through the inferior edge of the lachrymal bone just within 
the border of the orbit. 
There is no postorbital process either of the frontal or malar bone. In 
adult animals, the sutures of the superior wall of the cranium are entirely 
obliterated, excepting in the anterior part of the nasal bones. 
The premaxillaries are not coossified on the middle line, but are in 
contact. They send a slender process backward from the inner apex, inclos¬ 
ing the foramen incisivum on the inner side, whether completely or not is 
