SIWALIK SELENODONT SUINA, ETC. 
17—158 
Species 1. — Hyopotamus pal^eindicus. n. sp. Nobis. 
History. — This species was first named by the writer in the year 1877 1 on the 
evidence of two small upper molar teeth, obtained by Mr. W. T. Blanford in the 
lower Manchhar rocks of Sind. Other teeth, together with a portion of the mandible, 
were subsequently obtained from the same strata by Messrs. Blanford and Fedden, 
and have also been briefly noticed in the “ Records.” 2 All the above specimens form 
the subject of the present fuller notice. 
Tipper molars. — In figures 4 and 6 of plate XXIII. of this memoir there are 
represented, from the masticating aspect, the two most perfect specimens of the 
above-mentioned upper true molars. The specimen represented in figure 4 belongs 
to the right side, has been but little abraded by wear, and is most probably the last 
true molar. The specimen represented in figure 6 is from the opposite side, has 
been considerably more worn down, and is probably the second true molar : both 
specimens are quite perfect. The external aspect of the specimen represented in 
figure 4 is given in figure 7. These teeth present all the essential characters of the 
upper molars of the genus Hyopotamus ; the fifth, or accessory column, is of relatively 
small size, but can be distinguished, in its unworn condition, on the right side of 
figure 4, but in figure 6 it has become confluent by wear with the antero-internal 
column f left side of figurej. The crown is remarkably low, surrounded on three sides 
by a well defined ‘cingulum,’ and invested with a striated enamel. Although, as has 
been already mentioned, these teeth present a strong resemblance in their general 
plan of structure to those of the European and American species of Hyopotamus , yet 
when examined in more detail they present such differences as to leave no doubt of 
the specific distinctness of the form to which they belonged, though it is much to be 
desired that materials may eventually be forthcoming which will enable more full 
comparisons to be made. The most important points of distinction of the Indian 
teeth are the much more prominent development of the vertical ridges on the external 
surfaces of the outer columns, and also the smaller relative size of the fifth 
column. The following comparisons indicate these differences in the species 
approaching in size to the Indian teeth. In all the three skulls figured by M. Filhol, 
in his memoir on the fossil mammals of Ronzon quoted above, 3 under the names of 
Hyopotamus ( AncodusJ lept.orhynchus , II. aymardi, and II. velaunus , the fifth column is 
very much more developed than in the Indian teeth, being frequently as large as the 
other columns, while, as far as can be judged from the figures, the median vertical 
ridges on the external surfaces of the outer lobes, so conspicuous in the Indian teeth, 
appear to be wanting. In the molars of the large R. boirinus 4 from the Isle of Wight 
these ridges are likewise wanting. In the molars in the British Museum belonging to 
the form described by Professor Owen under the name of H. vectianusf hut identified by 
i ‘ R. Gr. S. I.’, Vol. X., p. 77. 2 Vol. XI., p. 80. 
3 Pis. XV. to XVII. An excellent woodcut of an upper molar of H. velaunus is given by M. Gaudry, he. cit. , p. 98, 
fig. 122. 4 Owen loc. cit., pi. VII., fig. 1. 5 Ibid, pi. VTI„ fig. 6. 
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