44 



straight, and is but little out of the line of the molars. There 

 is a very long diastema between the incisors and the canine, 

 and here the premaxillary is deeply notched to allow the pas- 

 sage of the lower canine. 



The Malar is very different in shape and size from the same 

 bone in Palceosyops. Its facial extent is greater, as it articu- 

 lates with the maxillary as far forward as the first molar. 

 It is not so broad from above downwards, but is considerably 

 thicker; the articulation with the squamosal is by flat sur- 

 faces. The postorbital process is small and indistinct. The 

 orbit is of great size ; its breadth, shown by the maxillary 

 floor is unusual, but its fore-and-aft diameter is extreme, 

 being nearly twice as great as in a large Palceosyops major. 



The Squamosal is a short, slender, and trihedral bone ; it is 

 not at all like the squamosal of Palceosyops. It is smaller 

 even than that of P. paludosus ; its outer margin is not turned 

 up, making the upper surface concave ; it does not project 

 much outward, and scarcely at all downwards, as this is ren- 

 dered unnecessary by the flatness of the forehead. The chief 

 difference, in the size of this bone, between this genus and 

 Palceosyops is found in the much greater vertical and lateral 

 diameter of the latter ; in length they are about equal. The 

 glenoid cavity is large, shallow, and transverse. 



As a whole, the zygomatic arch is comparatively slender ; 

 it is rounded, and does not project much laterally from the 

 side of the head ; but its chief peculiarity consists in the fact 

 that it is nearly horizontal. It is thus altogether different 

 from the arch of Palceosyops. 



The Occipital Condyles are different from those of that genus. 

 They are flatter, shorter from above downwards, and propor- 

 tionately much smaller ; but are expanded laterally in much 

 the same manner. At the border of the foramen magnum 

 they are gently rounded instead of having a sharp angle. 

 These borders are segments of circles, but as the condyles are 

 broken from the rest of the occiput, we cannot infer from this 

 the shape of the foramen. 



The Mandible is long, stout, but comparatively shallow. 

 It is of nearly uniform thickness throughout, and does not 

 exhibit the thickening of the alveolus and thinning, of the 

 lower margin, which is shown in Palceosyops, especially in P. 



