1834.] On the Fresh-water Shells of India. 91 



having kept it for a year, I found on immersing it in water, that the 

 shells imbedded in it, were still alive and healthy. Diameter f inch. 

 No. 11. — Var.? Planorbis. 



These I brought from Mirzapoor, and have marked them as a variety, 

 on account of their form being more regular, than the last ; they were 

 found plentifully, and may probably prove the young of Planorbis 

 No. 10. 



No. 12. — Planorbis. 



The whorls in this species are very much flattened. — The aperture 

 opening obliquely and oval — shell thin and diaphanous — whorls 4 or 

 5 in number — diameter 3| lines. 



The exuvia common on the Ganges. — They are found in stagnant 

 waters — more frequently in nullahs than in jheels. 



No. 13. — Planorbis. 



Animal blackish. The shell minute, 'of three or four whorls, which are 

 rounded ; aperture oblique ; diameter about 1^ line. 



These very small shells I found during the hot winds of 1833, in 

 the earthen pans containing the water for my tatties. They were 

 drawn from a well in my compound, [the bottom of which is hard trap- 

 rock, and also from one other well near my house. How they got into 

 these wells I cannot conceive, as there is no nullah or pond near them. 

 They were not abundant. 



No. 14. — Melania. 



These I found on the banks of the Ganges among exuviae. They are 

 injured by exposure to the sun. They inhabit rivers. 



No. 14. 



A smaller size. These appear to be the same as the foregoing. I ob- 

 tained them during the hot winds, from the same well in which the 

 small Planorbis, No. 13, was taken. This is a curious fact, as the bot- 

 tom of the well is hard trap-rock, and unless the animals burrow into 

 the sides of the well, they cannot possibly find protection at the bottom 

 of it. In this well there is no true spring, it being supplied merely by 

 the water soaking down from the surface during the rains. 



No. 15. — Melania. 



I have one specimen, which was given ne by a friend of Mr. Ben- 

 son's, from whom he obtained it. The epidermis is dark olive green. 

 Shell 2 inches long. The body whorl longitudinally tuberculated. 



No. 16.— Melania. 

 ^ This species, of which I have only one specimen, is of a blackish colour. 

 Transversely wrinkled on the whorls. Length 1| inch. 



This I found in a nullah at Chunar, which with the exception of the 

 rainy season, at which time it joins the Ganges, is strictly "stagnant 

 water." The animal was alive, and in soft mud. 



