194 BRITISH MOLLUSKS. 



The British Paludince are : — 



1. contecta. Shell scalariformly turbinated, of five to sis tu- 



midly produced whorls, convoluted around a deep umbilicus. 



2. vivipara. Shell obtusely ovately turbinated, of four to five 



moderately ventricose whorls, closely convoluted, leaving 

 merely a compressed umbilical chink. 



ffib, 



1. Faludina contecta. Covered Paludina. 



Shell ; scalariformly turbinated, openly deeply umbibcated, rather 

 thin, dark olive-green, encircled with three purple-red bands, 

 whorls five to six, longitudinally densely plicately striated, 

 tumidly produced, obtusely angled round the upper part, with 

 the sutures impressed ; aperture somewhat pyriformly rounded, 

 lip simple, a little expanded. 



Nerita vivipara, Muller (1774), Verm. Hist, part ii. p. 182. 



Cochlea vivipara, Da Costa (1778), Test. Brit. p. 81. pi. vi. f. 2. 



Helix vivipara, Schroter (1779), Gesch. Fluss- Conch, p. 330. pi. viii. f. 2. 



Cyclostoma viviparum, Draparnaud (1801), Tail. Moll. p. 40. 



Natica vivipara, Ferussac (1801), Mem. Soc. Med. vol. iv. f. 395. 



Cyclostoma contectum, Millet (1813), Moll. Maine et Loire, p. 5. 



Lymncea vivipara, Fleming (1814), Edin. Hncyc. vol. vii. p. 77. 



Paludina vivipara, Stucler (1820), Kurz. Verz. p. 91 (uot of Say). 



Paludina crystallina, Gray (1821), Lond. Med. Repos. vol. xv. p. 239. 



Vivipara communis, Dupuy (1851), vol. v. p. 537. pi. xxvii. f. 5. 



Paludina Listen, Forbes and Hanley (1853), Hist. Brit. Moll. vol. iii. p. 8. 

 pi. Ixxi. f. 16. 



Hah. Europe, chiefly in central parts. England, chiefly midland and 

 southern counties, not in Scotland or Ireland. (In canals, ponds, 

 and gently running waters.) 



