32 VIVIPARID^E. 



garis. Gray, Med. Rep. 1821, p. 239. ; Leach, Syn. Moll 207. 

 Paludina fasciata. Desk., Lam. vii. 513. Nerita fasciata. 

 Miiller, Verm. 182. Cyclostoma achatinum. Drop. 36. 1. 1. 

 f. 18. Turbo achatinus. Sheppard, Linn. Tram. xiv. 125. t. 



I. f. 18. Paludina achatina. Brug. E.M. t. 458. f. 1.; Lam. 

 H. vii. 174.; Rossm. 109. f. 66*. ; Turton, Man. 133. f. 119. 

 Helix vivipara b. Gmelin. S. N. 36. 46. Nerita fasciata. 

 Sturm. Faun. vi. 2. t. 12. Cochlea vivipara. Da Costa B. C. 

 71. t. 6. f. 2. Vivipara fluviorum. De Montf. 246. Limnaca 

 vivipara. Flem. E. Ency. vii. 77. Paludina vivipara. Say, 

 Amer. Conch, t. 10; Forbes and Hanley, Brot. Moll. iii. 



I 1. t. 71. f. 14. 15. t. H. H. f. 2. Vivipara fasciata. Dupuy. 

 Moll. Franc. 540. t. 27. f. 8. 



Younu shell with numerous hairy bands : Helix compact ills 



Pulteney, Col. Dorset. 48. 

 Very young shell : Vitrina femorata. Auctor. 



Inhabits the upper parts of rivers, where the 

 water is not brackish. 



Shell resembling the last, but of a more oblong 

 shape, with six volutions, which are not so much 

 swollen, and consequently the sutures are not so deep. 

 The young shells are furnished with numerous close 

 ciliated spiral lines. Lister gives the anatomy of the 

 former species, and Cuvier of this (t. 6. f. 1. 4.), in 

 the Mem. Mollusques. 



Though Lister has figured the two species as found 

 in Britain, they had been confounded by English 

 conchologists until I noticed them in the Medical 

 Repository for 1821, when I also pointed out that they 

 were known to Lister, and that the young shell of 

 the two species offered the very different characters 

 noticed in their descriptions. They are sometimes 

 found together in the same river, as at Uxbridge, 

 Middlesex. 



Messrs. Forbes and Hanley have changed the 

 name which I gave to the new species, because the 



