Feb. 16, 1872.] 417 [Cope. 
influence would not suffice to raise a tide of a quarter-inch at the Sun’s 
surface. But variations of inertia (m d*) and of power to produce local 
oscillations (- oi ) may be much more important, in their influence on 
ae 
fluid bodies, than differential tidal variations ( se) At the very out- 
set of my cosmical investigations (wite, ix., 287), I gave a method for es- 
timating the Sun’s distance by comparing the atmospheric inertia rela- 
tively to the Earth, with the same inertia relatively to the Sun. The re- 
markable coincidence of the disturbing focus of the Wolfian cycle with 
the centre of linear oscillation in the planetary system, seems to render 
it probable that solar explosions and spots are also determined by laws of 
inertia and local oscillation. 
ON BATHMODON, AN EXTINCT GENUS OF UNGULATES. 
By Epwarp D. Cope. 
(Read before the American Philosophical Society, Feb. 16, 1872.) 
The present form embraces some of the largest Perissodactyles, or odd- 
toed Ungulata, of our Tertiary Strata. It is represented by remains of 
two species, which include portions of the cranium, with teeth and frag- 
ments of jaws; vertebrae, fragments of scapular and pelvic arches and 
bones of the limbs. The distal end of the tibia is wanting, but that of 
the fibula indicates an odd-toed animal, and the third trochanter on the 
exterior ridge of the femur confirms the reference. 
There are probably four superior molars, though three only are pre- 
served. Two premolars only remain of the superior species, but the frag- 
ment of ramus mandibuli, referred to the same species, exhibits four pre- 
molars ; from a consideration of the sizes of the superior premolars it is 
probable that there were four of these also. There are three strong inci- 
sors in each premaxillary. No canine tooth is preserved, but the pos- 
terior suture of the premaxillary bone is so wide as to point to an equally 
stout anterior part of the maxillary, fitted to support such a tooth. The 
dental series increases regularly in size, from befo:e backwards, the last 
being a little larger than the penultimate. The crowns of the molars 
exhibit on the outer margin a single, acutely-angled crescent, directed 
inwards, with a conic lobe alongside of, and anterior to its base, repre- 
senting a second external crescent. The crescent lobe proper is large and 
very obliquely directed, so that its external face is almost horizontal. 
The apex of its companion cone is continuous with its posterior margin, 
so as to be undistinguishable from it in some cases. The inner crescents 
are represented by a wide angular ridge, which is at a lower level than the 
exterior, and is little or not developed on the posterior side of the crown. 
A. P, S.—VOL. XII.—3A 
