284 THE SCOTTISH NATURALIST 



November 1916); Loch Mhor, small, numerous, labelled 

 "a usual lake form, dwarfed" (*V.) ; Borve Bay, one, small 

 type {id.). 



St Kilda. Hirta Island, small variety, July 1905 (J. 

 Waterston). 

 Limncea truncatula. 



Lewis. Near Grimersta, on grass, 3rd July 1918, two, 

 small (F. Montague Dyke); Port .Arnol, 7th September 1918, 

 several (id.). 



North Uist. Balelone, small, July 1905 (J. Waterston). 



Barra. Sinclair Loch, roth May 1894, one, small (Thomas 

 Scott). 

 Planorbis glaber. 



Barra. Sinclair Loch, 10th May 1S94, one (Thomas 

 Scott). 

 Planorbis crista. 



Barra. Sinclair Loch, 10th May 1S94, one each, type 

 and var. cristata (Thomas Scott). 

 A ncylus fluviatilis . 



Lewis. Near Grimersta, in fast-flowing burn, 3rd July 

 1918, several, with a few var. vitracea (F. Montague Dyke). 

 Mr Dyke tells me he also found it on stones in fast-running 

 burns near Linshader, 20th July 1918. 



North Uist. Stream running out of Loch Fada, 24th 

 May 1894, numerous (Thomas Scott). 



Unio margaritifer. 



Lewis. Lindale River, Loch Roag, fairly common, but 

 small (F. Montague Dyke, October 19 18). 



Mr Dyke tells me that in conversation with keepers he was 

 informed that this was by no means the only river in Lewis 

 where these mussels occur. One intelligent man told him 

 that they are never found in salmon rivers. He found no 

 pearls in the dozen or so specimens he collected. Speaking 

 of pearls, he added that nearly every specimen of Mytilus 

 cditlis taken in Loch Roag (near Grimersta) contained at least 

 one pearl, one as many as a dozen ! Of these, half a dozen 

 were about 3 mm. in diameter. 

 Pi si dium fontinale. 



Barra. Sinclair Loch, 10th May 1894 (Thomas Scott). 



Pisidium casertanum. 



Lewis. In muddy ditch, Linshader, 20th July 1918, with 

 P. personahun, numerous (F. Montague Dyke). 



