32 
VIVIPARID^. 
garls. Gray ^ Med. Bep, 1821, p. 239. ; Leach.^ Syn. Moll. 207. 
— Paludina fasciata. Desh.^ Lam. vii. 513. — Nerita fasciata. 
Muller., Verm. 182. — Cyclostoma achatinum. Drap. 36. 1. 1. 
f. 18. — Turbo achatinus. Sheppard., Linn. Trans, xiv. 125. t. 
I. f. 18. — Paludina achatina. Brag. 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. — Yivipara fluviorum. De Montf. 246. — Limnasa 
vivipara. Flem. E. Ency. vii. 77. — Paludina vivipara. Say., 
Amer. Conch, t. 10; Forhes and Hanley, Brot. Moll. iii. 
I I. t. 71. f. 14. 15. t. H. H. f. 2. — Vivipara fasciata. Dupuy. 
Moll. Franc. 540. t. 27. f. 8. 
Young shell with numerous hairy bands : Helix compactilis. 
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 
