FPvOM THE PLIOCENE OF INDIA. 541 



unnecessar)^ to describe the form of the vertebral scutes, as they are 

 not generally visible in specimens of the shells of existing species. 

 On the plastron the only important point that can be detected, is 

 that the inner border of the postgular plate (fig. 2, pg) is very short 

 antero-posteriorly, and was probably exceeded in length by the 

 intergular sutnre. 



As I have already mentioned, the fossil is certainly distinct from 

 all the Siwalik chelonians vrhich have yet been described, and I have 

 been unable to identify it with any existing Asiatic species. It 

 apparently comes nearest to C. sinensis'^, but differs by the much 

 narrower nuchal plate, and by the first vertebral being narrowest 

 anteriorly, as well as by the greater breadth of the whole shell and 

 the less gibbous profile of the hinder half of the carapace ; both forms 

 agree in the nature of the costal areolae and the shortness of the 

 inner border of the postgulars t. 



There are indistinct lateral keels in the existing species, but it is 

 quite possible that these would be invisible in a fossil condition. 

 C. pygoloi^lia, Peters J, from the Miocene of Styria is apparently an 

 allied form, which is, however, markedly distinct from the fossil 

 under consideration. 



Since, then, no other existing species appears to come as close as 

 C. sinensis to the Perim fossil, while it is improbable that the latter 

 should be identical with a non-Asiatic form, I think it may be 

 regarded as a new species, for which I propose the name of Clemmys 

 Watsoni, in honour of the donor of the type specimen. 



The species may be defined from the characters of the shell as 

 follows : — " Shell moderately vaulted, globose, broad ; posterior 

 margin entire ; nuchal plate narrow, and broadest posteriorly ; first 

 vertebral 'narrowest anteriorly, and showing a tendency to a bell- 

 shape ; second and third vertebrals hexagonal, fourth short, narrowest 

 posteriorly, and giving off a process jutting into the posterior border 

 of the third ; an interrupted vertebral, but no costal keel ; costal 

 areolae well-marked ; suture separating the postgulars much shorter 

 than the intergular suture." 



I may add that Col. Watson has presented the specimen to the 

 British Museum. 



EXPLANATION OF PLATE XV. 



€lemmys Watsoni, Lyd. — The carapace (fig. 1) and anterior part of the plastron 

 (fig. 2) ; from the Siwaliks of Perim Island, Gulf of Cambay, India. ^ nat. 

 size, pg, postgular plate. British Museum. 



* Compare Gray ' Cat. Sbield-Eeptiles Brit. Mus.' pt. i. pi. vii. 



t Morenia Berdmorei makes some approaf^li to the fossil in several characters, 

 but is at once distinguished by the greater length of the inner border of the 

 postgulars. 



X Denkschr. k. Ak. Wiss. Wien, vol. xxix. pi. ii. (1869). 



