LYMN.ECEA. 15 



1. Physa fontinalis, pi. Ill, f. 13, 14. 



Physafontinalis, Drapernaud, p. 54, pi. 3, f. 8, 9 ; Lamarck, 

 An. San. Vert., VI, pt. 2nd, p. 156; Pfeiffer, p. 94, pi. 4, f. 28; 

 Brard, p. 167, pi. 7, f. 7, 8 ; Brown, Illust. Conch., p. 30, pi. 

 14, f. 54, 55 ; lb., First Ed., pi. 41, f. 54, 55 ; Fleming, Brit. 

 An., p. 276; Leach, Moll., p. 150; Turton, Man., p. 127, f. 1 10; 

 Jeffreys, Linn. Tr., XVI, p. 379 ; Alder, Mag. Zool. and Bot., 

 II, p. 114; Forbes, Mai. Mon., p. 14; Thompson, Ann. and 

 Mag. Nat. Hist., VI, p. 48 ; Bulla fontinalis, Montagu, Test. 

 Brit., p. 226; Brown, Wernerian Mem., II, p. 516; lb., Ency. 

 Brit., VI, p. 433 ; Fleming, Edin. Ency., VII, p. 85 ; Limnea 

 fontinalis, Sowerby, Gen., f. 8; Planorhis bulla, Miiller, Verm., 

 'll, p. 167. 



Variety 1, pi. Ill, f. 11, 12. Shell somewhat more injlated, 

 and of a very pale horn colour, apjjroaching to white. 



Physa alba, Turton, Zool. Joum., II, p. 363, pi. 13, f. 3; 

 lb., Man., p. 128, f. Ill ; Brown, Illust. Conch., p. 30, pi. 14, 

 f. 56, 57. 



Found in the river Towin, North Wales. 



Variety 2, pi. Ill, f. 15, 16. Volutions more oblique ; body 

 less infated ; base more acute ; and spire more obtuse. 



Helix BullcBoides, Donovan, Brit. Sh., pi. 168, f. 2; Bulla 

 ftuviatiles, Turton, Conch. Diet., p. 27, the young shell; Brown, 

 Illust. Conch., p. 30, pi. 14, f. 83, 84. 



It is plentiful in a stream at Clonooney, King's County, 

 Ireland. 



Shell sinistral, oblong-oval, extremely thin, transparent, fragile, 

 and glossy, and of a greenish horn colour ; body very large ; epirc 

 very short, consisting of three or four volutions, the lower one a 

 little inflated, and terminating in a somewhat obtuse apex; aper- 

 ture oblong, occupying about three-fourths the length of the 

 shell, contracted, and pointed above, and rounded at the base. 

 Length about three-eighths of an inch ; breadth not quite a 

 quarter. 



Old shells are not unfrequently provided with a few longitudi- 

 nal and transverse wrinkles. 



This species is pretty generally diffused throughout Great 

 Britain and Ireland, in rivers, streams, and stagnant pools, adher- 

 ing to the under surface of aquatic plants. 



