218 Linnaan Society. 



P. marginatus. Abundant in dikes at Beeston, and of large size 

 in a stagnant ditch between Beeston and Attenborough. 



P. vortex. Very abundant in the river Trent, and in dikes at 

 Beeston, Lenton and Attenborough, and under the Seven Arches in 

 Nottingham Meadows. 



P. spirorbis. Abundant in the river Trent at Beeston, and in 

 dikes at Beeston, Lenton, and Attenborough. 



P. albus. In few numbers in the river Trent near Beeston. 



P. contortus. Not common on the bogs at Bulwell, and rare in 

 a ditch at Lenton. 



P. imhricatus. Not common on dead leaves in the lake at High- 

 field House. 



P. nitidus. Rare in the lake at Highfield House and in a pond 

 at Wollaton. 



(^Bivalves.) 



Cyclas rivicola. Rather abundant in the river Trent near Bees- 

 ton and in the river Soar at Thrumpton. 



C cornea. Very common in the river Trent near Beeston, and in 

 brooks at Lenton, Beeston, Attenborough, Bulwell, and Highfield 

 House, and under the Seven Arches in Nottingham Meadows. 



C. lacustris. Very abundant in a brook at Beeston and another 

 at Highfield House. 



Pisidium amnicum. Abundant in the river Trent at Beeston, in a 

 ditch near Beeston railway station, and in a brook at Beeston. 



Anodon cygneus. Abundant in the lake at Highfield House, in 

 the Old Trent at Sawley, and in mill-dams at Bulwell. 



A. cellensis. Abundant in the lake at Highfield House and in 

 the river Trent near Beeston. 



A . anatinus. Abundant in the lake at Highfield House, a stream 

 and canal at Lenton, and the rivers Trent and Soar. 



A. avonensis. Rare in the river Trent near Beeston. 



A . anatinus, var. (very ventricose). In the lake at Highfield House. 



Unio pictorum. Common in the lake at Highfield House, the river 

 Trent at Beeston and Sawley, and the river Soar at Thrumpton. 



U. tumidus. Not uncommon in the river Trent near Beeston, and 

 rare in the lake at Highfield House. 



U. avails. Found in the lake at Highfield House and in the river 

 Trent at Beeston. 



U. Deshayesii (if a var.). Not common in the river Trent near 

 Beeston. 



Dreissena polymorpha. Very common and large in the lake at 

 Highfield House, common in the canal at Lenton (where it is small), 

 the river Soar at Thrumpton, and a pond at Wollaton, and in few 

 numbers in the river Trent near Beeston. 



Land Shells. 

 Helix aspersa. Very common at Beeston and around Nottingham. 

 H. hortensis. Rare at Bulwell. 

 H. nemoralis. Very abundant in most hedges. 

 H. hybrida (if a var.). Rare at Highfield House. 

 H. arbustorum. Rare at Thrumpton, Sawley, and Highfield House, 



