29 



ujipcr pt'cmdlar is represented in Fig. 5, Plate V; a t'nignieiit of a second 

 upper molar in Fig. 6, Plate XXIII, and two lower premolars and a molar 

 ill Figs. 3 to 5, of tlic same plate. The teeth apparently all belonged to the 

 same individual, which had reached maturity, but had not advanced so llxr as 

 to have the summits of the tooth-lobes worn through so as to expose the 

 dentine. The enamel is longitudinally wrinkled on the sides of the true 

 molars and in a less degree on the premolars. 



The last upper premolar (Fig. 5, Plate V) has a trilolate crown consisting 

 of an outer pair of acute pyramidal lobes, and an inner larger conical lobe 

 embraced by a basal ridge in front and l^ehind. 



The fragment of an ui)per molar (Fig. 6, Plate XXIII) consists of the tore 

 jiart of the crown, and is composed of an outer crcscentoid pyramidal lobe 

 and an inner smaller conical lobe. A strong convex buttress forms tiie aiitero- 

 external angle of the crown, and a moderate basal ridge bounds it in front. 

 A conspicuous tubercle, the rudiment of an additional lobe, occu|>ies the angu- 

 lar interval between the principal lobes and the basal ridge. 



The lower molar tooth (Fig. 5) has a fore and ait bilobed crown as in 

 PaliEotheriuin and Titanotherium. The lobes arc crcscentoid pyramidal, and 

 the anterior is the smaller. 



The lower premolars have the same essential constitution as the true molar, 

 but are less well developed. In the fourth premolar (Fig. 4) the relative size 

 of the lobes is reversed, the anterior being the larger, and the postero-internal 

 liuttress of the crown is obsolete. In the third premolar (Fig. 3) the j^jste- 

 rior lobe is still more reduced in size, the anterior lobe is proportionately 

 enlarged, and the inner buttresses of the crown are obsolete. 



The measurements of the specimens are as follows : 



Lines. 



Fore and aft diameter of second uppci' luolar, estimated 17 



Transverse diameter of second upper molar IS 



Fore and aft diameter of last upper premolar !»A 



Transverse diameter of last upper premolar ■ 1'2 



Fore and aft diameter of second lower molar 10 



Transverse diameter of second lower molar 10 



Fore and aft diameter of fourth lowei' premolar ". 9i 



Trauisverse diameter of fourtli lower premolar (>i 



Fore and aft diameter of third lower premolar ..... S| 



Transverse diameter of third lower premolar. ; ~> 



Shortly after the original description of the above specimens, several others 



