16 



mentioned, the river Trent, opposite Clifton deeps, 

 amongst algae ; the Musco-sic brook, near Beeston ; a 

 dyke which runs below Beeston ; a brook near High- 

 field House ; a moist ditch below the Beeston Railway 

 Station; and amongst grass-roots on the bogs at Bul- 

 well. It is a common English shell, although near 

 here it is nowhere to be found in great abundance. 



Pisidium pusillum is procured at Kendal (Gough), 

 Northumberland and Durham (Alder), Preston (Gil- 

 bertson), Scarborough (Bean), near London (Brown), 

 Coggeshall, Essex (Hanley), Exmouth (Clark), Pen- 

 zance (Millet), Swansea (Jeffreys), near Bantry Bay 

 (Jeffreys), Aberdeenshire (MacgiUivray), and is abun- 

 dant in Ireland and Scotland. 



Forbes represents it as an inhabitant of Northern 

 and Central Europe. 



There is thus, in the neighbourhood of Nottingham 

 every branch of the family included under the head 

 Cyeladidae belonging to the British Isles. 



As the Pisidia are all small, I have preferred giving 

 a reference to Forbes and Hanley's " British Mollusca," 

 or Grey's edition of " Turton's Shells," for magnified 

 drawings oi' each of them, to publishing natural-sized 

 illustrations myself. 



MiTILIDJE. 



Amongst the fresh-water shells of Great Britain, 

 there is only a solitary individual belonging to this class, 

 and it is not strictly Brilishs being introduced about 

 thirty years ago. 



