1869.] Proceedings of the Asiatic Society. 165 



H. qfflnis, which by some authors were considered to be identical, 

 are believed by the author to be distinct, and figures of the shells and 

 animals are given. In conclusion Capt. Fryer appends directions for 

 collecting these interesting animals during sea voyages. 



Mr. Baxter bore testimony to the very great accuracy and care 

 evinced by Capt. Fryer, in his paper, particularly as to the times of 

 the appearance and disappearance of this very interesting class of 

 Molluscs. He took the opportunity of dissenting from the placing 

 H. teniobrancliia as a distinct species, believing it would prove to be a 

 variety of H. tridentata ; the absence of specimens was a great bar to 

 a correct conclusion. H. mucronata, although described by Quoy and 

 Gaimard, was entirely ignored by Rang and Souleyet. 



The thanks of the Society were voted to Capt. Fryer for his 

 •interesting contribution. 



II, — Notes on the topographical features of Assam, and their indica- 

 tions ; by J. Mekedith, M. D. (Abstract). 



Dr. Meredith proposes to explain the formation of the valley of 

 Assam by the well-known theoretic geological hypothesis of the con- 

 traction of the earth's surface, this being, Dr, M. says, the chief cause 

 of depressions and elevations. Dr. M. thinks that there are indications 

 of glacial action at Bishnath-Dolpore and at Tezpore, similar to those 

 which Prof. Agassiz has recorded as occurring in Brazil. Dr. M. 

 gives then an elementary explanation of certain ravines and swampy 

 places, called Hoolulis and Peetanies by the natives of Assam. He 

 also says that a good deal of the unevenness and disturbances of the 

 ground are due to seismic action. 



During the reading of the paper, Dr. Stoliczka observed, regarding 

 Prof. Agassiz' explanation of the formation of the Amazon valley by 

 glacial action, that a short time ago he had received information from 

 Mr. W. Gabb to the effect, that marine shells had been found in those 

 clayey beds which were supposed by Prof. Agassiz to be the result of 

 glacial action. This occurrence of marine fossils clearly shews, that at 

 least some portion of these deposits is of marine origin. 



Mr. H. B. Medlicott stated that the rocks at Tezpore which Dr. 

 Meredith most likely supposes to be moraines, are rocks in situ, and 

 that he (Mr. Medlicott) has not observed on them any glacial action 

 about Tezpore, nor in any other parts of Assam. 



