{ SEP 8 mo 



JOURNAL 



OP THE 



ASIATIC SOCIETY OF BENGAL. 



.«@< 



Part II.— NATURAL SCIENCE. 

 No. IV.— 1889. 



XIX. — -On the Tortoises described as Cliaibassia. 

 By R. Ltdekkek, B. A., F. G. S. 

 [Received September 4tli j— Read Nov. Gtli, 1889.] 

 (With two Wood-cuts.) 



In endeavouring to determine the true aiSnities of the shell of a 

 fossil tortoise in the British Museum, obtained many years ago from the 

 Siwalik Hills, and which I have described and figured in the ' Palajon- 

 tologia Indica '* as a form apparently allied to Nicoria (Clemmys) tri- 

 jiiga, a certain peculiarity in the relation of the hypoplastrals to the 

 carapace suggested that it might prove to be identical with the im- 

 perfectly known existing form described as Ghaihassia tricarmata 

 (Blyth). Unfortunately, the British Museum possesses no recent exam- 

 ple of that form, and I, therefore, wrote to my friend Mr. J. Wood- 

 Mason, requesting the loan of a specimen by the aid of which it could be 

 decided whether the fossil shell was or was not an allied type. In reply 

 to this application, I received two specimens, one of which was the shell 

 of a female collected by Prof. V. Ball in Sirguja, Chota Nagpur, while 

 the second was a male specimen, preserved in spirit, which was obtained 

 from the Naga Hills in Assam, and was one of the types of Ohaibassia 

 theobaldi, Anderson. 



A comparison of the two specimens with the Siwalik fossil at once 

 showed that we had to do with a form so closely allied to Ohaibassia 

 tricarinata that it was in all probability specifically identical ; and the 

 question then arose whether there was any justification for the separation 



* Series x, vol. iii. p. 176, pi. xxi, fig. 4, 



42 



