124 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



NOTES. 



Note on the occurrence of Pisidium fersonatum, Malm, in 

 THE British Islands. {Read Sth May, 1908.) — For some time 

 past in the course of my studies of the British representatives of the 

 genus Pisidium it has been borne in upon me that more than one form 

 had been included under the species P. nitidum, Jenyns. Recently, 

 thanks to a specimen most kindly sent me by Dr. A. C. Johansen, and 

 a second example in the Norman collection at the Natural History 

 Museum, I have been able to determine satisfactorily that the form 

 which was perplexing me belonged to the distinct species to which 

 Malm in 1855 gave the name of P. personatum. The task of picking the 

 examples out from others of my series is not yet complete, but the following 

 is a list of the localities from which it has so far been recognized : —Barnes 

 Common (Surrey); Keston (Kent) ; Colchester (Essex) ; Sigglesthorne 

 Stokon (Norfolk) ; Fordingbridge (Hants) ; Bristol (Gloucestershire) ; 

 Sutton Coldfield (Warwickshire) ; Lancaster (Lanes) ; Huddersfield and 

 Swinton (Yorks) ; Lochmaber (Dumfriesshire) ; Glenshesk (Antrim) ; 

 Enagh (Londonderry) ; MacDara's I. (Galway) ; Brown's Bay (Sligo) ; 

 Portmarnock (Dublin). 



In the Holocene it occurs at Copford and in the Kennet Valley. The 

 species is therefore widely distributed and probably common in these 

 Islands, though hitherto overlooked. 



B. B. Woodward. 



