198—44 INDIAN TEETIARY AND POST-TERTIARY VERTEBRATA. 
precisely with that of recent specimens, consisting of tubercles not arranged in 
distinct lines, of conical form near the periphery of the carapace, but irregular on 
and near the median line : there is a tendency to a concentrically linear arrangement 
of the tubercles on the plastral callosities. The nuchal scute apparently agrees 
precisely in form with that of the living forms. 
Second specimen. — Another shell in the British Museum (No. 39833), also from 
the Siwalik Hills, exhibits the greater part of the carapace, and the plastron which 
has been crushed in. The azygos entoplastral callosity is unfortunately wanting, 
but since the shell agrees precisely in other respects with the figured specimen it may 
very probably be referred to the same species. The anterior paired plastral callosities 
form a less open angle at their posterior junction than in the figured specimen, and 
thereby agree with the living form. The two fossil specimens agree very closely 
in respect of size. 
Xipliiplastral callosity provisionally referred to this species. — A specimen of a right 
posterior, or xiphiplastral, callosity in the Indian Museum (No. E 144), obtained by 
Mr. Theobald from the Siwaliks of the Punjab, agrees in size and the structure of 
the sculpture Avith the corresponding callosity of full-sized existing specimens of 
Emyda, and may, therefore, be provisionally referred to the present species. The 
relation of the rugose callosity to the underlying xiphiplastron indicates that the 
specimen belonged to a fully adult individual ; its longer diameter measures 2T inches. 
Anterior marginal scute provisionally referred to this species. — In plate XXVI. figs. 4. 
4a. there is represented from the dorsal and posterior aspects a specimen of the right 
anterior marginal scute of an Emyda, also obtained by Mr. Theobald from the Siwaliks 
of the Punjab. The specimen agrees exactly in general form and the structure and 
arrangement of the sculpture with the corresponding scute of the recent forms. As 
its extreme length is 2’45 inches, and the length of the corresponding scute of a 
specimen of E. granosa., of which the carapace measures 6 inches in length, is 
1'2 inches, the specimen would agree in relative size with a full-sized individual of 
E. vittata, and may, therefore, be provisionally referred to the present species. As 
particular characters of this form of scute it may be observed that there is a groove 
along the whole of the posterior border (figure 4a.fi for cartilaginous union with 
the adjacent marginal scute; and that on the dorsal aspect (fig. 4fi the sculpture 
does not extend up to the inner border, while it does so extend on the ventral 
aspect. On the dorsal aspect the sculpture consists of low regularly shaped 
tubercles, without the slightest trace of a linear arrangement. The dorsal aspect is 
convex longitudinally, and concave transversely. 
Distribution. — In India the existing E. vittata is found in Ceylon, Southern, and 
Central India; being replaced in the North-West, the Punjab, and elsewhere by E. 
granosa. The fossil indicates that E. vittata originally ranged over Northern India; 
and it may perhaps be concluded that E. granosa is a race of more modern 
origin. 
