SIWALIK AND NAKBADA EQUIDfiE. 
11—77 
use. The isolation of the anterior c pillars ’ in these teeth shows that they belong to 
a Ripp other him, while the existence of a larger form of milk-molars of the genus in 
the Siwaliks (to be noticed in the sequel) renders it probable that these teeth belong 
to the present smaller species. 
The first milk* molar (mm. 1) is a small sub-cylindrically shaped tooth : the 
second milk-molar (mm. 2) is elongated ; the third and fourth teeth of this series 
(mm. 3 : nun. 4) approach a square in cross = section. 
As it is mainly from the characters of the upper milk-molars that the distinct- 
ness of the next species is inferred, it will be necessary to examine the characters of 
these teeth somewhat more closely. In all the' three larger teeth the anterior ‘ pillar * 
is subcylindrical, and is placed far in between the two inner ‘ crescents,’ so that by 
the presence of a large amount of cement the inner wall of the crown presents a 
smooth face, without any projection of the hinder border of the anterior £ pillar.’ 
In the second milk-molar there is an infolding of enamel on the inner side of the 
produced anterior extremity of the crown : the posterior c pillar ’ presents the pecu- 
liar character of being separated from the posterior inner ‘ crescent.’ In the second 
and third milk-molars the posterior ' pillar ’ does not extend backwards as far as the 
hinder border of the crown. In all these teeth the plications of the enamel in the 
central islands are of great complexity. The teeth are coated very thickly with 
cement, which nearly obliterates the ridges on their outer walls. 
The dimensions of the specimen are as follows : — 
Width *of palate between 1st milk-molars 1'82 
„ „ „ last „ • 20 
Length „ four milk-molars . 3'72 
„ „ three last „ 3 52 
„ „ 1st milk-molar 0'48 • 
Width „ „ 0-32 
Length „ 2nd 1'42 
Width „ „ 0-89 
Length „ 3rd 101 
Width „ „ 0'94 
Length „ 4th 1*1 
Width „ „ O' 94 
Mandible . — In figures 14 and 14a of plate LXXXII of the “Fauna Antiqua 
Sivalensis ” two views are given of a fragmentary mandible of a small equine animal 
referred to the present species. In the description of the plate the specimen is 
said to contain the three premolars and the first true molar : an inspection of the 
figure, however, shows clearly that the fourth tooth (the first true molar) is less 
worn than the preceding tooth ; hence the three anterior teeth must be milk-molars, 
and not premolars. I am unable to say whether the specimen belongs to this or 
the next species. 
In figure 3 of plate XII of this volume there is drawn a fragment of the left 
ramus of . the mandible of an equine animal collected by Mr. Theobald in the 
