Zoological Society. 143 



sity was not immediately gained. It lasted a short time, and, 

 as in the case of slender tourmalines, the needle rapidly re- 

 ceded, and in a short time returned to zero. 



The very satisfactory results which I have obtained from all 

 these minerals give me great confidence in the aptitude and 

 accuracy of my simple apparatus ; and from the very con- 

 siderable intensity which I find them all to possess, I expect 

 to be able to estimate much smaller degrees of pyro-electricity 

 in other minerals, and in artificial crystals, than have yet been 

 attempted. 



Should my first results have appeared interesting to the So- 

 ciety, I may perhaps at no distant time have the honour of 

 communicating my further progress in the inquiry. 

 Greenhill, January 2, 1832. 



XXIII. Proceedings of Learned Societies. 



ZOOLOGICAL SOCIETY. 



1834. SPECIMENS and drawings were exhibited of a fresh- 

 March 1 1 . — ^ water Tortoise, forming part of the collection of Mr. 

 Bell, by whom it was described as the type of a new genus, for which 

 he proposed the name of 



Cyclemys. 



Sternum latum, testam dorsalem longitudine fere aequans, inte- 

 grum, solidum j testae dorsali ligamento squamato connexum. 



Cyclemys orbiculata. Cycl. iestd suborbiculari, carinatd, postice 

 dentatd, fused; scutis sternijlavescentibus, fusco radiatim lineatis. 



Long, dorsi, 8 unc. j lat. 7 j alt. 3. 



Emys orbiculata, Bell. 



Pullus. Emys Dhor, Gray, Syn. Rept., p. 20.? 



Hab. in India. 



Mr. Bell regards the Tortoise which he has thus characterized as 

 supplying a link in the connecting series of the land with the fresh- 

 water families which has hitherto been wanting ; and as especially 

 valuable in the natural arrangement, by the clue which it furnishes 

 to the correct location of the Indian forms of the genus Emys. It is, 

 indeed, most nearly related to Emys spinosa, and on a superficial ob- 

 servation might almost be referred to that species ; but on closer 

 examination it is found to differ from that Tortoise, not only specifi- 

 cally, but generically also : its sternal bones are permanently sepa- 

 rated from the dorsal ones, with which they are connected by means 

 of a ligament alone, similar to that which performs the same office in 

 Terrapene. From the Box- Tortoises, however, to which, in this point 

 of its structure, it is so closely related, Cyclemys is altogether distinct, 

 the whole of its sternum being entire, instead of having, as is invari- 

 ably the case in Terrapene, one or more transverse divisions of the 

 sternum itself, the lobes of which move as on a hinge. In Terr. 

 Europaa this mobility of the sternum exists in each lobe in a small 

 degree, combined with the ligamentous connexion of the sternal to 



