of British Mollusca. 337 



248. Cionella luhrica {Miill.). 



Subgenus Azeca, Leach. 



249. Cionella tridens (Pulteney). 



For notes on this species see Taylor, ' Journal of Con- 

 cliology,' vol. ii. p. 220. A reversed monstrosity has been 

 found by Mr. J. Emmet, of Boston Spa. 



Genus 2. C^cilianella, Fc^russac. 



250. Ccecilianella acicula (Miiller). 



Fam. 6. SuccineidaB. 

 Genus Succinea, Draparnaud. 



251. Succinea putris (Linn.). 



252. Succinea elegans, Risso. 



Westerlund separates S. elegans and S. Pfeifferi, Rossm., 

 and gives seven named varieties of the former and seventeen 

 of the latter. I cannot myself, after an examination of twelve 

 of these named varieties, find any points which seem to me to 

 constitute specific characters between these most variable 

 shells, and therefore I follow Jeffreys in using the earlier 

 name. 



253. Succinea stagnalis, Gassies. 



Succinea putris, \ax. vitrea, Jeffreys, Brit. Conch, vol. i. (1872), p. 152, 

 Succinea virescens, Jeffreys, Ann. & Mag. Nat. Hist, ser. 6, vol. ii. 



(1878), p. 378 (nee S. virescens, Morelet, Jide Baudon). 

 Succinea stagnalis, Gassies, Malac. Terr, et d'Eau douce de la r^g. int. 



litt. de I'Aquitaine, p. 14, tig. 2. 

 Succinea stagnalis, Baudon, Deuxieme Supplement a la Mon. des 



Succin^es Fran^aises (1879), p. 1, pi. xi. figs. 1-3. 



Jeffreys gives the following localities : — Carmarthenshire, 

 Grassmere, and St. Albans {J. G. J.), Cork {Humphreys) ^ 

 Mitcham, in Surrey {Henry Groves). 



The SuccinecB are most difficult to distinguish and the forms 

 run into each other, so that I am myself disposed to hold that 

 we have but two species, S. putr-is and S. ohlonga. Succinea 

 stagnalis affords a good illustration of confusion. Jeffreys first 

 referred it to S. putris as var. vitrea (I suppose taking that name 

 from Moquin-Tandon) ; then receiving from Baudon the shell 

 described by him as S. debilis, said that his shell was the same, 

 but that it was not S. debilis (Morelet, MS.) C. Pfeiffer, the 



