192—38 INDIAN TERTIAEY AND POST-TERTIARY VERTEBRATA. 
agrees in tlie obtuse angle formed by tlie suture between the postgular and j)ectoral 
jolates, in the absence of a vertebral keel in the adult, in the rounded plastron of the 
adult, and in the proportionate length of the inguinal and axillary incisions. The 
recent species differs by its decidedly more depressed shell, tlie highest point of 
which is placed somewhat more anteriorly ; the nuchal jdate is, moreover, somewhat 
narrower, the 1st and 2nd vertebrals more narrowed at their junction, the 3rd more 
distinctly hexagonal, the 4th somewhat more narrowed anteriorly, and the angle 
formed by the suture between the postgulars and pectorals more obtuse. 
Tliat the present form is closely allied to B. kacJmga, of which it may probably 
be considered the ancestral form, there seems no reasonable doubt ; and as in the 
case of B. falconeri the question arises whether to consider the Siwalik form as a race 
or a sj^ecies. The view taken in the one case must.be adoj^ted in the other, and the 
present form is therefore regarded as a species, which, in honour of the collector of 
the type specimen, it is proposed to designate Batagur hakeri. 
Distribution . — As above-mentioned, the one specimen on which this species is 
founded was obtained from the typical Siwalik Hills. The range of the existing B. 
kachuga covers that of the fossil. 
Species 3. Batagur dueandi, n. sp. nohis. 
(Allied to Batagur dhongoka, Gray.). 
Shell. — This third Siwalik species of Batagur is founded on a shell from the 
Siwalik Hills presented to the British Museum by Col. Sir P. T. Cautley, and figured 
of one-fourth the natural size in plate XXIV. fig. 2. The specimen comprises the 
greater part of the carapace, which shows the boundaries of the greater number of 
the bony scutes, as well as those of most of the overlying plates : the greater part 
of the plastron is also preserved, but since it does not show the form of the plates it 
has not been figured. Tlie condition of the sutures indicates a subadult specimen ; 
and the length of the shell is about 16 inches. 
The shell is of an extremely depressed form, very like that of the existing B. 
dhongoka^ by which character alone it is widely distinguished from the two preceding 
species. The suture between the postgular and pectoral plates was probably straight ; 
the xiphiplastron is notched, although less deeply than in B. dhongoka. The 1st 
vertebral plate is of an elongated bell-shape, and very narrow anteriorly ; the 2nd 
and 3rd vertebral plates are elongated, the hinder border of the second being 
produced into a long projection formed by a keel in the underlying scute, and 
penetrating far into the 3rd plate ; the latter bears the same relation to fhe under- 
lying scutes^ as obtains in B. dhongoka and the other members of section a of group 
A. Of the 4th vertebral plate only the anterior half is shown; its junction with the 
3rd vertebral is narrow, and the lateral borders of the anterior half diverge 
posteriorly, and indicate tliat this plate was of the elongate form characteristic of 
B. dhongoka and its allies. The posterior border of the 1st costal suture commences 
1 Vide nil jira, i). 191. 
