31 



the Rev. Mr. Racket, in 1797, in the " Lirmean 

 Transactions." 



Pisidium cinereum, added by Mr. Alder, in 1838, in 

 his supplement of the " Newcastle Shells." 



Pisidium Henslowianum, added by the Rev. Mr. 

 Sheppard, in 1825, in his list of " Svffolk Shells." 



Pisidium nitidum, described by Mr. Jenyns, in 1832, 

 in his " Monograph on Cyclas and Pisidium." 



Pisidium obtusaie, added by Captain Brovrn, in 1831, 

 and described in the ♦' Edinburgh Journal of Geogra- 

 phical Science.^' 



Pisidium pulchellum, added by Captain Brown, in 

 1831, and described with P. obtusaie. 



PisitJium pusillum, described by Dr. Turton, in 1822. 



Dreissena polymorpha, added by Mr, J. de C. 

 Sowerby, in 1824. 



Unlo tamidus, described by Dr. Lister, in 1678. 



Uoio pictoruQj, described by Dr. Lister, in 1678. 



Anodonta cygnea, described by Merret, in 1667. 



Mr. Grey states that Pisidium cinereum, P. Henslow- 

 ianum, P. nitidum, and P, pulcheJlum, are not found 

 in Friance or Germany, and that Unio pictorum and U. 

 tumidus does not exist as far north as Scotland. 



W,e Have now completed tbe history of our bivalve 

 shells, a history which is almost complete for Great 

 Britain, inasmuch as this locality contains fourteen out 

 of the fifteen British bivalves; the deficient species 

 being one which belongs to the family of Unionidae. 



