284 



IRISH PISIDIA FROM WINDERMERE. 



Rev. C. E. Y. KKNDALL, B,A. 

 Oundlc. 



Among a quantity of shells of the genus Pisidium, which I 

 lately sent to Mr. A. W. Stelfox for identification, are a number 

 from Windermere, which he pronounces to be Pisidium 

 hiberniciim Westerlund and P. liUjeborgi Clessin. The shells 

 were afterwards passed on to Mr. R. A. Phillips and Mr. Charles 

 Oldham, both of whom confirmed his identification. I collected 

 them in October, 1913, from the western (Lancashire) shore of 

 the lake, in shallow water, near Sawrey-on-Windermere, 

 where they were present together, associated with Pisidium 

 pulchelhim Jenyns and P. subtruncatum Malm. Neither of 

 the species has, I believe, been hitherto recorded for North 

 Lancashire. 



Pisidium hiberniciim, though regarded as an Irish mollusk, 

 seems to have a very wide range of distribution in England 

 and Wales. It has been found at many stations in eight of 

 the Midland and two of the Southern counties.* In Wales 

 it is very prevalent in the mountain tarns. It has, however, 

 onl}' been recorded so far for the North of England from one 

 locality in the Isle of Man, and from Hawes Water, Silverdale, 

 in Mid-Lancashire ; but it is almost certain that, if northern 

 naturalists would collect this genus freely, this species would 

 be found to be as universally distributed in England as in 

 Ireland. 



, Pisidium liUjeborgi, which was the more abundant shell of 

 the two, is also a species with an extensive range in Ireland, 

 but seems to be distinctly rare in Great Britain. Mr. B. B. 

 Woodward, in his British Museum publication, ' A Catalogue 

 of British Species of Pisidium ' (1913), gives one locality for 

 it in Mid-Lancashire, viz., Hawes Water, Silverdale, and records 

 it from three stations in Carnarvonshire and from four in 

 Scotland. Mr. Stelfox tells me that he has recently seen it 

 from Malham Tarn in Yorkshire, and I have just received some 

 specimens from Mr. Oldham, from Patterdale, in Westmorland. 

 P. liUjeborgi is probably a Northern and Alpine species, and 

 shows a strong preference for clear water with a clean gravelly 

 or sandy bottom, so it is probable that this species, too, will 

 be found before long in many more localities in the Lake 

 District and Scotland. 



Mr. Stelfox, Ballymagee, Bangor, co. Down, asks me to say 

 that he will be glad to receive for purposes of study collections 

 of Pisidia, and will return the same after identifying them. 



* See 'The Range of Pisidium hiberniciim,' by Messrs. Phillips and 

 Stelfox in The Irish Naturalist of March, 191 8. 



Naturalist, 



