298 Oir THE SZTTLL OV OETCTBHOPTTS GAUDRTI. [Feb. 18, 



position of tbe condyle, wbich is borne upon a much shorter pedicle 

 and has a more horizontal articular surface. 



Tbe minute structure of the teeth is precisely as in 0. capensis, 

 so that they give no indications of the possible origin of their 

 peculiar character. 



In tbe left maxilla six teeth remain in place, and in front of them 

 is an empty alveolus ; on the right there are five teeth and two 

 alveoli. The most anterior tooth preserved is pm. 3 (counting 

 from behind forward); this is small and laterally compressed, its 

 flat crown slopes downward and forward. The next is similar, 

 but less compressed. The hindermost premolar is a stout simple 

 tooth ; its worn crown consists of two flat surfaces meeting in an 

 angle and forming a transverse ridge. The two first molars are very 

 similar to those of the recent species, but the last (m.^) is rather 

 different. In the living forms it is somewhat variable in shape, 

 but usually consists of a single column and is nearly circular iu 

 section ; in one skull from Somaliland, it is, however, oval in 

 section and shows traces, at least on the outer side, of division 

 into two lobes, the hinder being much the smaller. The circular 

 type of tooth evidently results from the reduction of the hinder 

 lobe, which in the fossil is only a little smaller than the anterior 

 one, from which it is separated by a well-marked vertical groove on 

 the outer side and a less distinct one on the inner. In a young 

 skull of a recent species, in which the last molars are only just 

 coming into use, they are distinctly bilobed, so that the upper part 

 of the crown of the unworn tooth resembles in form the worn 

 molar of the Pliocene species. 



In the mandible six teeth are preserved on both sides. The two 

 anterior ones are much compressed ; the next is stouter and its 

 grinding surfaces form a transverse ridge. The first two molars 

 are similar to those of the living species : the third (m.^) is clearly 

 bilobed and is nearly as long as m.,. In the recent species the 

 division into columns is distinct only on the inner side, and the tooth 

 is much shorter from before backward than the preceding one. 



The dimensions of the skull and mandible are : — 



Width between ends of postorbit.al processes . . 63 millim. 



Outside width at postglenoid processes 60 „ 



Width of cranium behind postorbital processes 36 „ 



Greatest width of occipital surface 52 „ 



Height of foramen magnum 13 „ 



Width „ „ 22 „ 



Distancebetweenpostorbitalprocessandzygoma 17 „ 



Mandible. 



Height at coronoid process 65 millim. 



„ „ condyle 52 „ 



Height of ramus behind last molar 16 „ 



,, „ in front of first molar 12 „ 



