BITHINIA. 27 



Bitbynia Leachii. Leach, Sijn. Moll. 209 ; Forbes and 

 Hunleij, B. M. iii. 16. t. 71. f. 78. t. H.H. f. 1. — Paludina 

 Trochelliana. Philippe. — Paludina Kickxii. Ve.stend, Bull. 

 Acad. Bnix. 1835, 375. — Paludina decipiens. Mich. Mag. 

 Zool. 1843, 2. t. 64. f. 2. —Paludina Michaudi. Duv. in 

 Rev. Geol. 1845, 211. — Bithinia Kickxii and B. Michaudi, 

 Dvpny., Moll. — Paludina acuta. Fleming. Br. Anim. 315. — 

 Cyclostonia simile. Drop. 31. t. 4. f. 15. (?) — Paludina 

 ventricosa. "Leach., MSS." Sheppa7'd, Broum, Brit. 

 Shells, t. 41. f. 74, 75. — Paludina humilis. N. Boubee, Cat. 

 —Paludina similis. Turton, Man. 1^5. f. 121. Alder, Mag. 

 Zool. and Bot. ii. 116. 



In ditches and canals ; often even where the 

 water is slightly brackish ; south of England. ( Gray, 

 1821.) 



Shell a quarter of an inch long, and two lines 

 broad, with four or five very tumid volutions ; aper- 

 ture dilated, nearly circular, projecting more out- 

 wardly, or out of the line of the columnar axis, with 

 a small umbilicus behind it. 



The fry, or mass of o^gg, of this species, are dis- 

 posed on a tough strap-shaped green membrane, in a 

 double row, consisting of six or seven pairs placed 

 opposite to each other ; and this elongated receptacle 

 is fixed to the under surface of aquatic plants. 



Mr. Sheppard received it from Dr. Leach, under 

 my name, but he changed it to Turbo Leachii. I 

 do not think it is C. simile of Draparnaud : in Dr. 

 Turton's figure the volutions are scarcely sufficiently 

 ventricose. 



The shell is often covered with a ferruginous in- 

 crustation, and the apex of the spire is sometimes 

 eroded. 



Mr. Alder observes {Mag. Zool. and Bot. ii. 116.), 

 *' The Paludina viridis of Turton's Manual (ed. 1. 



