27 



The principal localities in this neighbourhood are — 

 a mill dam at Bulwell, and a stream near it, the lake 

 at Highfield House, the canal near Beeston and at 

 Lenton, the river Trent, the river Soar, a backwater 

 called " The Old Trent " near Sawley, a sheet of water 

 at Radford Grove, another at Cinder-bill, and a third 

 at Basford. 



The more distant localities are too numerous to 

 enumerate. 



According to Professor Forbes, a large specimen is 6 

 inches long, and 3 broad. Some obtained from the lake 

 at Highfield House were larger than this, and speci- 

 mens from a sheet of water in the park at Hartwell 

 (the seat of Dr. Lee) measured 6§ inches long, by 3^ 

 inches broad.. 



As the form of this shell varies very consideiably, 

 brief descriptions of some of tbem will be given. 



Specimens taken from a sheet of water in Hartwell 

 Park were 6| inches long by 3^ inches broad, and 2^ 

 inches across in the most ventricose part. They were 

 strongly indented with brownish longitudinal markings 

 on the lower half of the valves, some of the deepest 

 indents being nearly the eighth of an inch in depth ; 

 the upper half of the valves were very little indented, 

 and of a yellowish green colour. The ligament scarcely 

 raised above the shell, and nearly black, as also was the 

 colour of the upper part from the ligament to the fron 

 edge. The longitudinal marking was less shown in the 

 interior of the valves, though very apparent. The 

 upper edge of the valves was almost straight. The 

 colour of the interior of the valves a pearly-white. 

 The shell fragile. 



Specimens found at Dinton, in Buckinghamshire, fey 

 the Rev. J. Goodall, and sent to me by Dr. Lee, were 

 not nearly so much produced as those taken at Hart-- 

 well. The length was of inches, the breadth 3 inches. 



