20 
BRITISH MOLLUSCA. 
z z z — i i i i. Yorkshire. Presented by P. Carpenter, Esq. 
Cyclas stagnalis. 
jjjj — pppp ? Britain. Mus. Mont. 
2. Pisum. 
Pisum, Megerle , Entw. 57, 1811 (not Linn.); Gray , P. Z. S. 
1848, 184. 
Cyclas, sp., LamJc. Hist . ed. 2. v. 55.9 ; Leach, 1818, 1. c. xx. 272. 
Pisidium (amnicum), Pfeiffer, Naturg. i, 123. (1821) ii. 33. iii. 68; 
Desk. E. M. iii. 772 ; Nilsson, Moll. Suec. 99 ; Gray, Turt. 
Man. ed. 2. 279, 282, 1840. 
Galileja (fontinalis), Costa, Correspond. Zool. 1839 ; Phil. Moll. 
Sic. ii. 214. 
Pera (amnica), Leach, MSS. B. M. 1819, fide Gray, Turt. Man . 
282, 1840 ; Ann. Sf Mag. N. H. xx. 267. 
Euglesia (pusilla), Leach,MSS. B.M. 1820, fide Gray, Turt. Man. 
282, 1840; Ann. Sf Mag. N. H. xx. 267. 
1. Pisum obtusale. 
Pisidium obtusale, Pfeiffer, 125. t. 5. f. 21, 22 ; Jenyns, l. c. 301. 
t. 20. f. 1, 3 ; Gray, Man. L. Sf F. W. Shells, 282. t. 12. f. 149 ; 
Brown, III. Conch. G. B. 94. t. 39. f. 24 ; Forbes 8f Hanley, 
Brit. Moll. ii. 120. t. 36. f.l. 
Cyclas obtusalis, not Lam. Hist. v. 559. 
Pera gibba, Leach, MSS. Brit. Mus. 
Young. The yellow zone broader. 
Var. 1. Shell ovate, trigonal, very ventricose, blackish or 
ochraceous ; the edge very blunt. 
Cyclas obtusalis, Nilsson, 101 (not Larnk .) ; Hanley, Rec. Shells , 
i. 90. Supp. t. 9. f. 47. 
Cyclas obtusale /3, Jenyns, l.c. 13. 
a—f (Pera gibba). Britain. Presented by J. E. Gray, Esq. 
g — 1 1. Coggeshall, Essex. 
mm — uu. Watford, Herts. Presented by T. B. Hall, Esq. 
2. Pisum nitidum. 
Pisidium nitidum, Jenyns, Monng. 16. t. 20. f. 7> 8; Gray, Man. 
L. Sf F. W. Shells, 283. t. 12. f. 150; Thompson , Ann. Nat . 
Hist. vi. 195 ; Macgilliv. Moll. Aberd. 253; Brown, III. Conch. 
G. B. 95. t. 39. f. 26 ; Forbes Sf Hanley, Brit. Moll. ii. 126. 
t. 37. f. 14. 
Cvclas nitida, Hanley, Rec. Shells, i. 90, Supp. 1. 14. f. 46. 
Hab. ? 
3. Pisum pusillum. 
Tellin a pusilla, Turton, C. Diet. 167. 
