Dr. J. E. Gray on Trionyx Phayrei. 85 



" a. Adult. Length 21 inches, breadth 14^ inches ; length 

 of osseous sternum 124 inches." 



It appears that Mr. Theobald only obtained one specimen, 

 which he informed me he gave to the Bristol Museum ; so 

 that Dr. Anderson cannot have a better means of determining 

 this species than the above description affords. Mr. Theobald 

 showed me his specimen as Chitra indica^ and I was quite 

 unable to decide, in the dried state, to what Asiatic species it 

 belonged, as the skull was enclosed and could not be examined, 

 and the animals vary so little in their external appearance 

 when they have lost the characteristic markings of their 

 coloration, which only can be observed in their young state. 

 The great resemblance in their external appearance is mani- 

 fest from the fact that Mr. Theobald compares it with such 

 distinct things as Trionyx gangeticus^ Dogania subplana^ 

 Chitra indicaj and Pelochelys Cantori^ belonging to two 

 families of very different structure and habits. 



But the chief character that he seems to rely upon as the 

 characteristic of the species is the part of the above description 

 which I have marked in italics, i. e. the slight development of 

 the sternal callosities. 



Dr. Anderson, in the ' Proceedings of the Zoological Society,' 

 1871, p. 154, describes a species he calls Trionyx Phayrei^ 

 observing that " the chief differences that separate it from T. 

 gangeticus are the less developed character of the osseous por- 

 tion of the sternum, and the relatively finer character of its 

 sculpturing on both aspects." He gives a figure of the sternum, 

 which does not accord with this remark, but represents it as 

 having not only large and well-developed lateral callosities, 

 not in the slightest degree resembling the small narrow 

 linear lateral callosities found in Dogania as described by 

 Mr. Theobald, but also having large triangular anal callo- 

 sities and the odd osseous semicircular bone in the front 

 of the sternum covered with a lunate callosity not even 

 found in Trionyx gangeticus ; so that this animal can have no 

 connexion with the species described by Mr. Theobald, except 

 that it comes from a nearly similar part of Hindostan. But, 

 unfortunately, that is no criterion of their identity, as many 

 species of TrionycidcB and Chitradce are found in that district, 

 as has been proved by Cantor and Mr. Theobald himself. 

 The fact is, that the specimen described by Dr. Anderson is 

 a specimen of my genus Landemania^ and probably the spe- 

 cies which has been named L. perocellatus. 



I know how much the sternal callosities change during 

 growth ; but a person who has examined many species of the 

 three-toed tortoises in different stages can form a very good 



