KniCBUCK MKMOUrAl, NtlMRKN. I77 



PI. vortex. 71. Running water, sometimes in ponds, in England 

 generally and in Korfar and in (Caithness : in Ireland mostly in 

 Shannon basin ; records for Londonderry, Down, Kildare, 

 Wexford, Kilkenny, Cork E. and M. want confirmation. 



PI. leucostoma {spirorbis). 125. Still and stagnant water and 

 summer-drying ponds generally ; sparse in north Scotland. 



Bathyomphalus {Planorbis) contortus. 120. Usually in 

 running water also ponds and ditches generally. 



Hippeutis {Planorbis) fontanus {niHdus). 97. Ponds and ditches 

 generally north to Ross. 



Segmentina {Planorbis) nitida {lineatus). 27. Rare in ponds 

 and slow streams, mostly in eastern counties, as far north as 

 Yorks. M.W. ; not in Ireland ; museum records for Elgin, Wilts. 

 N. and S. and Dorset want confirmation. 



Physa fontinalis. 119. Running water and lakes north to 



Perth N. generally. 

 Ph. heterostropha. 4. North American alien living in open in 



Gloucester W., Cheshire, Lanes. S. (since 1897) and Glamorgan. 



Ph. acuta. S. Alien in greenhouse tanks and warm water, Surrey, 

 etc., Lanark and Dublin. 



Aplexa {Physa) hypnorum. 97. Local in stagnant ponds and 

 ditches, often dry in summer, north to Perth and doubtfully to 

 Elgin. 



Paludestrina {Hydrobia) ventrosa. 15. Brackish water north 

 to Lincoln, and in Ireland. 



P. jenkinsi. 68. Originally in brackish water {Journal, vi (1889), 

 142), has since spread widely into rivers, streams and canals ; 

 north to Cumberland, also in Perth M. and generally in Ireland. 



P. stagnalis {itlvce). 41. Brackish and salt water from Cornwall 

 and Kent to Ross, and in Ireland. 



P. confusa {siini/is, a?iatina). 8. Brackish and nearly fresh water, 

 Sussex W., Kent W. (probably extinct), Suffolk E., Norfolk E., 

 Kilkenny, Clare, Limerick and Waterford. 



Amnicola taylori. 2. Probably an alien, of unknown origin, has 

 lived in canals near Manchester since 1900 {Journal, xi, 9 ; 

 Lanes. /Vat., xi (19 18) 71). 



Bithinia tentaculata. 104. Slow running water, lakes and 

 ponds north to Stirling generally. 



B. leachii. 47. Rather local in slow running water, south, central 

 and east England, north to York ; rare in Ireland. 



