Illustrated Index of British Shells / Containing figures of all the recent species

by G. B. Sowerby

03. I. pallida, Harvey.—I. patula.—Clare, Rr. as Brit.

04. I. exigua, Lamk.—Cornwall, Clare, etc., Mr.

Neritina. In rivers.

05. N. fluviatilis, Linn.—N. fontinalis.—Thames, Trent, Humber, etc., Scotch lakes, Cc.

Bithinia. In ponds.

06. B. Leachii, Shepp. (Turbo.)—B. ventricosus, Paludina acuta, similis, etc.—Rivers S. Brit., Mr. Narrow, with rounded whorls.

07. B. tentaculata, Linn. (Helix.)—T. nucleus, Paludina impura, etc.—Fresh-water, throughout Brit. Oval.

Paludina. In ponds.

08. P. Listeri, Forbes and Hanley.—Helix vivipara, etc.—Lakes and ponds generally, Mc. Whorls more separate, umbilicus larger than P. vivipara.

09. P. vivipara, Linn.—Pal. achatina, etc.—Thames, etc., C.