146 F. Stoliczka — Notes on terrestrial Ifollusca. [No. 2, 



an influence upon the development of locally, and now persistently, 

 distinct forms, which evidently descended from a common stock, 

 will best become evident from a few instances, which are worthy of 

 record. 



At Moulmein about the great Pagoda occurs a species of Cyclo- 

 phorus which Mr. Theobald called C. Ilaughtoni. The specimens 

 are generally lighter or darker brown, and, except on the keel, un- 

 spotted. At the ' Farm-caves' the same* species occurs, but always 

 marked with numerous white spots, and at Damotha a third form is 

 met with, being generally somewhat smaller and higher, and provid- 

 ed with small pale spots or reticulated streaks ; this form has been 

 named by Mr. Theobald C. affinis. Again, at the ' Farm-caves' oc- 

 cur in great abundance Sophina calias and discoidalis, Sesara pylaica, 

 Clausilia Philippiana, Streptaxis Sanlceyanus, Pollicaria gravida, Ra- 

 phaulus chrysalis, fyc, none of which are found on a perfectly similar 

 limestone hill at Damotha, barely 15 miles distant from the for- 

 mer. There we find Sophina for abil is, Sessara infrendens, Georissa 

 liratula, Biplommatina carneola, Bhiostoma Ilaughtoni, and other 

 peculiar forms, &c. South of Moulmein, again on similar lime- 

 stone hills, occurs Sophina conjungens, while calias and discoidalis 

 are rare, Streptaxis obtusus, Sfc, but not a single Pollicaria or Ra- 

 phaulus or Bhiostoma. Again at another limestone hill on the 

 Attaran river there is only a peculiar banded variety of Sophina 

 discoidalis to be found, Strept. Sanlceyanus is replaced by the allied 

 Strept. Hanleyanus, Sesara pylaica by Sesara Attaranensis, Theob. &c. 

 I could multiply the examples, but those quoted will indicate that 

 the molluscous fauna of each limestone hill, or range of hills, 

 possesses certain forms representative of, or allied to, others which 

 occur on a neighbouring hill, while at the same time it has a 

 certain number of local, peculiar, species. This is a condition which 

 we are generally accustomed to find on small separate islands 

 within an Archipelago. 



In conclusion I may observe that the present communication 

 contains species of both of the large divisions of pulmoniferous 

 Mollusca, the Cyclostomacea and the Helicacea. It will be 

 noticed that the work is somewhat unequally executed, but it is 

 done so with a certain object. 



