274 MOLLUSCA. PULMONIFERA. Limnea. 



Helix detrita, Pult. Dorst. 49. Mmt. Test. Brit. 384, tab. xi. £ 1 



III England and Ireland. 



Length |ths of an inch ; lines of growth numerous, fine, with minute Ion- 

 gitudinal striae, sometimes plain or with one, two, or three brown bands ; 

 whorls nearly flat ; aperture narrow ; pillar-lip reflected, forming a distinct 

 cavity behind. Mr Bryer found this shell in a pool near Weymouth, and in 

 a stream near Dorchester. Dr Turton adds, that it is found at Dublin. 

 Judging from English and foreign specimens sent to me by the late Rev. 

 James Lambert senior, Fellow of Trinity College, Cambridge, I am inclined to 

 consider the Helix detrita of Pultney, and the Bulim-us radiatus of Drapemaud, 

 as distinct species, the latter being a land shell. 



108. L. palustris. — Shell brown ; whorls six, tapering to a 

 sharp point. 



Bucc. minus fuscum. List. An. Ang. 139. Conch, tab. 124. £ 24. — H. 

 stagnalis, var. B., Penn. Brit. Zool. iv. 139. — H. pal. Mont. Test. Brit. 

 370, tab. xvi. £ 10 — H. fragilis et fontinalis, Don. Brit. Shells, tab. 175, 

 f. 1, 2. — In ditches and swamps. Common. 

 Length about |ths of an inch, with numerous lines of growth, and longitu- 

 dinal wrinkles ; whorls rounded ; peristome thickened, purplish. 



109. L. octona. — Whorls eight ; shell subcylindrical, pointed. 



Helix octona, Linn. Svst. i. 1248 — Bucc. glabrum. Mull. Verm. ii. 135. 

 H. oct. Penn. Brit. Zool. iv. 138, tab. Ixxxvi. £ 135. Pult. Dorst. 49- 

 — H. octanfracta, Mont. Test. Brit. 396, tab. xi. £ 8. — L. elongatus, 

 Drap. Moll. 53. — In slow running ditches. 

 Length |ths, breadth of the body-whorl about ith of an inch ; yellow- 

 ish-brown ; whorls rather flat, striated across ; mouth narrow ; fold on the 

 pillar elevated. Animal dusky ; foot short ; tentacula narrow, flat ; eyes at 

 the internal base, in a shallow cavity, covered by a small protuberance, re- 

 sembling the rudiments of tentacula. This seems a very local species. IMon- 

 tagu found it in Coniwall ; and it has occurred to me in several ditches in the 

 upper part of Linlithgowshire. The Physa scaturiginum of Drapemaud, 

 (Moll. 50), and named as British by Dr Turton (Zool. Joum. N'. VIII. 565.) 

 seems to be only the young of this species. 



110. L.Jbssaria. — Whorls five, rounded; pillar-lip broad, re- 

 flected. 



H. foss. Mont. Test. Brit. 372, tab. xvi. £ 9. — In shallow muddy pools. 

 Common. 

 Length fths of an inch ; whorls increasing more rapidly than in the preced- 

 ino- ; striated across, and wrinkled longitudinally ; separating Une deep ; mouth 

 wide ; lip, in descending on the pillar, broad and reflected, exhibiting the 

 oblique fold very indistinctly — This is probabh' the Turbo striatus quatuor 

 anfractibus apertura ovali marginata of Walker, Test. Min. tab. ii. £ 57, called 

 T. rivulus, by Montagu, and Limnea minuta by Drap. Moll. 53. — This spe- 

 cies and the L. octona frequently creep out of the water, and remain for some 

 time in a quiescent state. 



** Shell ventricose. 



111. L. limosa. — Whorls five; the first four rounded; mouth 



slightly contracted. 



H. lini. Linn. Syst. i. 1249. — Bucc. peregnim. Mull. Verm. ii. 130 — H . 

 putris, Penn. Brit. Zool. iv. 139, tab. Ixxxvi. £ 137 — H. peregra. 



