L T ^[ N j: a. 



Genns LLMN^^A, Ldinarck. 



Testa dextrorse spiralis, testaceo-comea, ovuUi sen pjira- 

 midata, epidei^mide teimiindiita ; spira acuminata, 

 anfractibus plerumque iurritis, labia interna aper- 

 tiirce super anfractum ultimum ant/iisti- ej-jxinso, 

 plerumqne unipUcato. Operculum nullum. 



Shell dextrally spiral, horny-testaceous, ovate or jiyra- 

 niidal, covered with a thin epidorniis ; spire 

 acuminated, whorls generally turreted, inner lip of 

 the aperture narrowly spread on the body-whorl, 

 generally with a single plait. No operculum. 



The LimncecB are to be found in every part of the 

 world where there are small streams of running water, 

 or stagnant pools, or inland lakes. Not only the genus 

 but the species have a very wide range, our British 

 species being mostly found in all parts of the Continent. 

 The characters of some American species so nearlv re- 

 semble the European forms as to be almost undistin- 

 guishable. Australian forms have an inflated character 

 almost peculiar to them ; and among the Indian species 

 are some conical and some boat-shaped forms, also 

 strikingly diflering from our plain horny species in 

 presenting some varieties in colouring. The species 

 separated under the name of Amphipepl.«;.\, Xihsan, 

 are characterized by a greater degree of polish on the 

 shell, caused by a lobe of the mantle covering part of 

 it. Our British L. glutinosa presents an example of 

 this, and the shell itself is nearly involute, having 

 scarcely any spire. 



Species 1. (Mus. Brit., and fig. /-, j.l. ii.) 



LlMN^.\ AURlcuL.^Ri.'i. Lim. tcstii lata, patul,i. palliiU 

 cornea; spira, brevissimd , anfractibus tribus, parris ; 

 ultimo anfractu inflato, breviusculo ; apiitiirn 

 maxima, labia externa late expanso ; plica caluinel- 

 lari validd, elevatd, tortua. 



The auricul.\r Limn^a. Shell broad patulate. pale 

 horn; spire very short, whorls three, small; last 



whorl iiillateil, rather short ; aperture- very lurgi', 

 outer lip broadly expanded; culuiin-llar I'ohl 

 strong, elevated, tortuous. 



DitAPAltNAUD. Mollusqucs do France. ])l. 2, f. 'Ix. 



Limnwa aiiricularia, Linna.'us. 



Jfab. Britain and other parts of Europe. 



Species 2. (Mus. Brit.) 



Ll.MN.EA (iLAHl'',!!. Lim. tCStd SUllCI/li il'l rici'l , i(ili/)(.<l<i, 



elongatti, pallidi; J'uled ; s/iini rlinili'i, ti/ii'rlnnnn 

 longitudine multo superauti : (i/i/'r^niihus ijuiiiijh. . 

 convexis, duobus medianis hitiii.-<,-iiH.<. diinhu^ npi- 

 calibus minutis ; idtimo anfractu andi, .^upn) a/ier- 

 turam eleratn ; aperturd oblongil, milirr l,iliiisriil<i, 

 plicA columeltari crassd, rectiuscnld. 



The shining Limnj:a. Shell subcylindrical, narrow, 

 elongated, pale fulvous ; spire elevated, much ex- 

 ceeding the aperture in length ; whorls tive. 

 convex, the middle two rather broad, the apical 

 two minute ; last whorl oval, elevated above the 

 aperture; aperture oblong, rather broad in front, 

 columellar fold thick, rather straight. 



MuLi.ER. Schroet. Huss., pi. 7, f. 15. 



Ilah. Great Britain. 



The British Limncea octanfracta and the American 



/,. elongata may possibly be varieties of this. 



Species 3. (Mus. Brit.) 



LiM.N^A tuuncatula. Lim. testd brevi, solidiuscubi, 

 pallidi fused, spird conicd, aperturam lonijiludint 

 jiaulo superanti, anfractibus quatuor, brcviuscidi.^, 

 rotundis ; ultimo anfractu breviter subci/lindracto : 

 aperturd oblongo-subquadratd, antice truncald, labia 

 interna crassiusculo, antice rectiusculo, plica cdii- 

 mellari hand prominenti. 



The truncated Lisixjia. Shell short, rather solid, pale 

 brown, spire conical, a little exceeding the apc-r- 



