86—20 INDIAN TERTIARY AND POST- TERTIART VERTEBRATA, 
tlie same differences occur between the present teeth and the lower molars of 
R. gracile. The jaw of R. theobaldi is further distinguished from that of R. gracile 
by the smaller interval separating the first of the molar series from the commence- 
ment of the symphysis. 
In figure 4 of plate XII there are represented the teeth of a broken right 
ramus of the mandible of an equine animal collected by Mr. Theobald at Jabi, 
in the Punjab. The specimen shows the last premolar (pm. 4) and the three 
true molars (m. 1, m. 2, m. 3). As no remains of the genus Rquus have been 
obtained from the district where this specimen was collected, it is inferred to belong 
to Rippotherium. In the dimensions of the jaw and length of the teeth, the 
specimen agrees with the above described jaw of R. theobaldi. The teeth differ, 
however, from those of the latter specimen by the enormous quantity of cement 
with which they are coated, especially noticeable in the premolar. The ‘ crescents ’ 
seem also to be less regular in form than in that specimen. A third mandible in 
the Indian Museum (No. C. 161) exhibits less cement than the specimen drawn in 
figure 2 of plate XII, and it, therefore, seems that the quantity of cement cannot 
be taken as a character of specific value, and all three specimens are consequently 
referred provisionally to one and the same species. 
Limb-bones. — Erom the fertile fossil locality of Niki, in the Punjab, so 
frequently alluded to in previous pages, Mr. Theobald has obtained several portions 
of limb-bones of a large hippothere, probably belonging to the same individual as 
the upper and lower jaws. These remains comprise the upper portion of a tibia, the 
distal ends of a pair of radii, and a hind and fore-foot in a more or less complete 
state. I have nothing to note on the first three of these specimens, but have a few 
remarks to make regarding the feet, one of which is figured in plate XIII, figure 3, 
of this volume. This specimen belongs to the fore-limb, as is determined by its 
difference from another foot with a complete metatarsal. The distal extremity of 
the metacarpus is all that remains of that bone : the first and second medial 
phalanges are complete, but the terminal phalange has been broken. On the right 
side are seen the three phalanges of one of the lateral digits, and on the opposite 
side the distal extremity of the lateral metacarpal. The central metacarpal bears 
flat facettes on its posterior aspect for articulation with the lateral bones. Erom 
the slenderness of the remaining lateral metacarpal it would seem that, as in 
R. gracile , these bones did not extend continuously along the whole length of the 
median metacarpal. The bones of this foot seem to be nearest in size to those of 
the stout variety of the Pikermi hippothere described by M. Gaudry. 1 
In the specimen of the hind-foot in the Indian Museum, the lateral digits are 
smaller than in the figured specimen of the fore-foot. 
Distinctness as a species and distribution. — The specimens examined above 
leave but little doubt as to the former existence of a second species of Siwalik 
hippothere, mainly distinguished from R. antilopinum by the difference in the 
1 “Animaux Fossiles et Geolcgie de l’Altique’,’ pi. xxxv, fig. 13. 
