176 DR. C. W. ANDREWS OX LOWER MIOCENE [June I914, 



rugose surface for the fibula. Of the shaft a length of only 10 to 

 12 centimetres is preserved ; its anterior face is nearly flat, while 

 its sides and posterior face form a continuous convexity from side 

 to side. The dimensions (in centimetres) of this tibia are : — 



Width of distal articulation from side to side 10'0 



Width of the same from front to back 8*0 



Width of shaft, 10 centimetres above the articulation 7*2 



Members of this sub-order are also represented in the collection 

 by fragmentary remains, which indicate the existence of several 

 distinct forms, but are too scanty to permit of definite deter- 

 minations being made. The Tragulidae are probably represented 

 by two or three species. Thus, an upper much-worn molar is 

 closely similar to one of jProdremotheriuni, and to this form also 

 may perhaps be referred the distal end of a humerus and some 

 small astragali. A lower molar of a somewhat larger animal from 

 Bed 15 at South Nira is very like the same tooth of Dorcatlieriv m 

 nani Kaup, and to this an astragalus may also be referred. There 

 is, moreover, the distal end of a tibia, which does not seem to 

 agree with either of these types. Finally, a well-preserved right 

 astragalus from Bed 13 at Nira appears to belong to an antelope- 

 like animal about the size of a large goat, and an imperfect 

 calcaneum may be referred to the same form. 



On the whole, the collection indicates that in the Lower Miocene, 

 as at present, the Artiodactyla formed the most important con- 

 stituent of the African fauna. 



Sub-order Peeissodacttia. 



This sub-order is represented by some scant}" remains of a 

 Rhinoceros. The chief specimens are a third right upper molar 

 (PL XXVIII, fig. 3), portions of the radius, and some odd foot- 

 bones. 



The molar is well preserved, and seems to have been freshly broken 

 from the jaw. The form of the rather hypsodont crown will be 

 best understood from the figure. It will be seen that it was 

 triangular in outline, with a strongly- developed cingulum on the 

 inner part of the anterior face ; there is also a slightly-developed 

 ridge of the cingulum at the inner end of the transverse valley. 

 On the postero-internal angle near the base of the crown is a small 

 prominence, which Prof. O. Abel regards as representing the hinder 

 end of the ectoloph ; if this be so, however, not only is the metaloph 

 very greatly reduced, but the crochet arises from the ectoloph — it 

 seems probable that, in this case at least, the prominence belongs 

 to the cingulum. The crochet is small, and there are distinct traces 

 of the crista. Comparison with the corresponding tooth of several 

 species of Rhinoceros shows thai the specimen here described most 

 nearly resembles m. t of Rli. schleiermacheri, but is somewhat larger 

 and differs in the presence of the cingulum at the inner end of the 



