232 PROCEEDINGS OP THE MALACOLOGICAL SOCIETY. 



104. PisiDiuM suBTEUNCATUM, Malm. 



Harefield, Uxbridge, West Drayton, near Colnbrook, Bedfont, 

 Bushey Park, Brent near Hendon, and at Edgware. Also from tlie 

 Eed Arches Pond at Hampstead (B. B. Woodward), Ealing and 

 Eulham Moat (W. M. Webb). 



105. PisiDiTTM PULCHELLTJM, Jenyns. 



Harefield, Bedfont, and Bushey Park. It is a very local species. 

 Another locality is West Drayton (B. B. Woodward). 



106. PisiDruM Casertanum (Poli) = P. fontinale, auct. = P. cinereum, 



Alder. 



This species is often identified as P. pusillum or P. pusillum, var. 

 cinerea. 



It is not uncommon ; we have it from Uxbridge, Bushey Park, 

 Hendon, and Hadley Wood. 



107. PisiDiTJM PUSILLUM (GmcL). 



Yiewsley. Genuine P. pusillum seems to be very rare in Middlesex. 



108. PisiDiUM NiTiDUM, Jeuyus. 



Uxbridge, West Drayton, near Colnbrook, Stanmore, Hampstead, and 

 Enfield, It is rather a local species. 



109. PiSIDIUM OBTUSALE, Pfr. 



Harefield, Greenford, Bushey Park, and Einchley Common. 



This is a pond-dwelling species, and is not common in the county. 



110. PisiDiuM Gassiesianum, Dupuy. 



Harefield, Acton, West Drayton, near Colnbrook, Bushey Park, 

 Stanmore, Brent near Hendon, Hampstead ponds, Edgware, Enfield, 

 and Ponders End. 



The commonest of our small Pisidia. 



