36 BRITISH FEESHWATRIi RHIZOPODA. 



ENGLAND. Isle of Man ; N. Yorkshire ; Cambridge- 

 shire ; Bedfordshire ; Shropshire ; Buckinghamshire ; 

 Somersetshire ; Devonshire. 



WALES. Anglesey. 



SCOTLAND. Orkney Islands ; Dumfries. 



IRELAND. Inishbofin, Galway ; Clare Isl., Achill Is!., 

 and Caher Isl., Mayo; Kerry. 



The hemispherical test, with the large, slightly- 

 invaginated aperture, serve to identify this species 

 with ease. The internal prolongation of the mem- 

 brane around the aperture towards the crown, usually 

 present in members of this genus, is entirely wanting. 



Although not uncommon, only a few individuals 

 have been observed in a living state and none with 

 their pseudopodia extended. 



B. DIFFLUGIN&. 



1. Difflugia oblonga var. tenuis Penard. 

 (Plate LXI, fig. 8.) 



Difflugia pyrifcrmis var. tenuis 



PENARD in Mem. Soc. Geneve, XXXI, i, n (1890), p. 138, pi. iii, 



ft. 47-49. 

 Diffluyia oblonga var. tenuis 



WAILES & PENARD in Proc. B. Irish Acad. XXXI, LXV (1911), 

 pp. 16, 34. 



Test similar to that of the type in form, but smaller 

 and usually transparent ; fundus frequently angular ; 

 plasma and pseudopodia normal. 



Length 40-60 JJL ; diameter 20-35 /u,. 



Habitat. Aquatic vegetation. 



IRELAND. Achill Island and Louisburgh, Mayo 

 (Penard). 



Penard (1890) describes the occurrence, on the 

 fundus of the tests of this variety, of small rod-like 

 parasites, but they appear to have been merely 

 accidental. 



