68—2 INDIAN TERTIARY AND POST-TERTIARY VERTEBRATA. 
an equine animal from the Siwaliks of the Irawadi valley is figured and referred to 
the genus Equus, without any specific designation. It is impossible to say whether 
this determination be correct, and whether the specimen does not belong rather to 
Hippotherium. In this uncertainty no description of this specimen will be given 
in the present memoir. 
In their “ Catalogue of the Eossil Siwalik Vertebrata in the Museum of the 
Asiatic Society of Bengal,” 1 Messrs. Ealconer and Walker described other remains 
of fossil Indian Equidse from the sub- Himalayan Siwaliks and from the ossiferous 
beds of Perim Island. Among those from the latter place, some specimens are referred 
to Equus, and others to Hippotherium antilopinum. . An examination of the original 
specimens referred to the former genus shows that they also belong to Hippotherium. 
In plate LXXXIV, figures 15 to 19 of the “ Eauna Antiqua Sivalensis” some 
fragmentary limb-bones of horses from the probably pleistocene deposits of Tibet, 
beyond the Niti pass, are figured under the generic title of Equus. Other bones 
doubtfully referred to the genera Equus and Hippotherium have also been obtained 
from the same deposits, but it is probable that these determinations are open to 
doubt. 3 Erom the imperfect and fragmentary condition of the above mentioned 
remains no attempt at their specific, or even generic, determination can be made, 
and they will, therefore, be not alluded to at length in this memoir. 
Previously to the publication of the “Eauna Antiqua Sivalensis,” two notices 
of the occurrence of fossil horses in India had appeared in the “ Journal of the 
Asiatic Society of Bengal ” for 1835. The first of these was in a letter from 
Dr. Ealconer, dated Masuri (Mussoorie), January 1835. 3 It mentions the discovery 
in the Kalawala (Kallowalla) pass of a molar tooth of a horse,- which the writer 
thought might belong to a new species. Erom the description it is evident that this 
tooth belonged to a Hippotherium. The second notice 4 is by the late Sir W. E. (then 
Lieutenant) Baker. An inspection of the plate accompanying that notice shows 
that the teeth mentioned and figured belong both to Equus and Hippotherium : the 
above mentioned tooth of the latter genus from the Kalawala pass is figured (fig. 18) 
in this notice. 
In 1846 Professor Owen® remarked that “ the teeth of the extinct slender- 
legged horse, or Hippothere, transmitted by Captain Cautley to the British Museum, 
are identical with those of the above species \_Hippotherium gracile~\ from the 
European miocene.” 
In 1862 Professor Gaudry 0 observed that the limb-bones of Hippotherium 
antilopinum of India very closely resembled those of the slender-limbed variety 
of H. gracile from Pikermi. 
1 The notices referring to the Equidas are copied in the “ Palaeontological Memoirs,” Vol. I, page 186, et seq. 
2 See a paper by the author, ‘Rec. Geol. Surv. Ind.,’ Vol. XIV, p. 178. 
3 ‘ Journ. As. Soc., Bengal,’ Vol. IV, p. 58. 
4 Ibid, p. 566, pi. XLV 
5 “ History of British Fossil Mammals and Birds,” p. 395. 
6 “ Animaux Fossiles, et Geologie de l’Attique,” p. 231. 
