BECENT DEPOSITS OP NERBUDDA VALLEY. 



287 



it would seem at a former period to have been less plentiful than at 

 present, as it now is extremely common throughout Central India and 

 the Punjab, and ranges even to Burma and the Red Sea. 



In the upper group however a few recent species occur which have 

 not been noticed in the lower, though they very possibly occur in it as 

 well ; among them Helix asperella Pffr. This shell is extremely rare 

 in a living state in the valley at present, and but one specimen was 

 found fossil, but it becomes more plentiful towards the west, in Katti- 

 war, where it also occurs fossil in beds of apparently the same age as 

 the lower group of the Nerbudda, but of marine origin (a). 



I will here add for the sake of comparison a list of shells noticed by 

 me, within the drainage area of the Nerbudda, which will be found to 

 include most of the species of common occurrence in Bengal. 



Land Shells. 

 Cyclotus subdiscoideus. Sow. 

 Bulimus Abyssinicus. Eupp. 



,, coenopictus. Hutton. 



„ insularis. Ehr. 



„ punctatus. Anton. 



,, gracilis. Hutton. 

 Boysia Bensoni Pffr. 

 Succinea vitrea. Pffr. 



„ crasshiscula. B. 

 Pupa bicolor. Hutton. 



„ planyunculus. B. 



„ diploos. B. 



„ batliyodon. 

 Achatina scutellus. B. 

 Helix asperella. Pffr. 



„ unicincta. B. 



,, bullata. 



Fresh water Shells. 

 Corbicula cor. Sow. 

 TJnio marginalis. Lam. 



„ corrugatus. Lam, 



„ coeruleus. Lea. 

 Melania tuberculata Mull. 



„ lirata B, 



„ spinulosa. Lam. 

 Lymnsea luteola. Lam. 



„ acuminata. Lam. 

 Paludina Bengalensis. Lam. 



• ,, melanostoma. B. 

 Bithinia cerameopoma. B. 



,, pulchella. 



„(?) (small indet). 

 Planorbis Coromandelicus. Fab. 



„ compressus. Hutton. 



„ convexiusculus. Ben. 

 Ancylus verruca. Ben. 



In contrasting the shells from this deposit with those found existing 

 at the present day in the district, the rarity or absence of many of the 

 commonest living species is very remarkable. 



(a) The same bed also contains other existing shells common in the district (Katti- 

 war) at present, as Cyclotus subdiscoideus Sow. Bulimus insularis Eh. B, Punctatus Anton 

 Helix fallaciosa Per. &c. A detailed description of this bed would be foreign to the present 

 Report, but reference may be made to the Geological Summary by Dr. Carter who has 

 described it under the term miliolite, or as it is commonly known at Bomba}-, Pore-Bunder 

 Stone, from the port whence it is shipped for importation into Bombay. 



