46 BRITISH FRESHWATER EHIZOPODA. 



for the presence of chlorophyllous food-particles ; the 

 pseudopodia simple, digitate. 



Dimensions : Length 90-1] 5 /A; breadth 80-95 p. 



In ponds, ditches, and marshy places, not infrequent. 

 Chipperfield, Herts (A. Earland). North and West 

 Yorkshire ; also Llyn Cwlyd and Capel Curig, North 

 Wales (G. 8. West). Loch Ness, Scotland (J. Murray). 



Leidy, in his description of this species, included 

 every form which had a three- to six-lobed mouth, 

 without paying much regard to structure that is to 

 say, whether the lobes were regular or irregular, 

 rounded or angular. There seems every justification, 



58 59 



FIGS. 58 AND 59. Oral views of Difflugia lobostoma showing great 

 variation in size : 58, from Carlton Banks, N. Yorks, x 520 ; 59, 

 from Sedburgh, W. Yorks, x 100. From drawings by G. S. West. 



from more recent investigations, for separating some 

 of the forms. 



D. gramen Penard, and others, differ from J). lobo- 

 stoma, in having tests which are overlaid with coarse 

 sand-grains, giving them a rough exterior, whilst 

 D. lobostoma is comparatively smooth, its lobed mouth 

 beautifully cut, and the entire structure more grace- 

 fully outlined. Leidy remarks that tests are some- 

 times met with of which the mouths are six-lobed.* 

 Some examples gathered by us in Richmond Park 

 presented this feature, and the fact of D. corona 

 Wallich being found in the same locality may give 

 colour to that author's 'surmise that D. corona and 

 D. lobostoma merge into oire another by intermediate 



* [He figures one with seven lobes (' Freshw. Ehiz. N. Amer.,' t. xv, f. 14).] 



