DO 



i'onn niid pi'dpoiiioiis willi the same jxirlioii ol' \\\c jaw in Palceoxi/o/is pnUi- 

 (losus, excei)tiiig that the masseteric fossa- is nuicli deeper. The preser- 

 vation of the angle of the jaw, not retained in any of thi^ previous specimens of 

 Palaeosyops, permits the determination of its character. It presents a nearly 

 serai-circular border projecting moderately below ti)e base of the bone, and in 

 a less degree posteriorly. Toward the base it is somewhat bent inward. 



The last molar, in a restored condition, of the natural size, is re|)resente<l 

 in Fig. 14, I'late XXIII, but, unfortunately, the artist has made its tliickness 

 in front proportionately too great. 



The measurements of the specimen are as t()llows: 



Fragments of another jaw similar to the above, and presenting the same 

 comparatively deep masseteric tbssa, were found by Dr. Corson at Grizzly 

 Buttes. 



Fig. 2, Plate XXIV, represents a mutilated facial portion of a skull appar- 

 ently referable to PalcBosyops major. The specimen was found on one of the 

 buttes of the Bridger formation by a Shoshone Indian, and brought to Dr. 

 Carter, by whom it was presented to the writer. Though much distorted in 

 form, it gives us a fair idea of the shape and construction of a portion of the 

 skull of Palseosyops that we had not previously had the opportunity of ex- 

 amining. It is crushed in such a manner that the upper part of the face is 

 pressed downward and toward the right side, and the orbit has its roof 

 brought near to the floor, so that it looks as if it were closed behind l)y the 

 presence of a postorbital bridge. 



The specimen shows that the form and construction of the face of Paloeo- 

 syops are very similar to what they are in Paleeotheiium. The upper part of 

 the face appears to have been directed in a moderately sigmoid course, nearly 

 horizontallv from the bottom of the convex forehead to the end of the muz- 



