40 BRITISH FRESHWATKH UHIZOPODA. 



truncate ; aperture hexagonal or lobed, of medium size, 

 bordered by an expanded lip with a wavy periphery ; 

 the neck very short with the base recessed into the 

 body of the test ; plasma normal, containing Zoo- 

 chlorella-cells in symbiotic relationship, also frequently 

 oil-like globules; nucleus single, large, granular; one 

 or more contractile vesicles usually present ; pseudo- 

 podia numerous, digitate, simple or branched. 

 Length 150-275 /z (Penard). 



Habitat. Aquatic vegetation and ooze of lakes and 

 ponds. 



WALES. Anglesey. 



This species as described by Penard (1902) has a 

 well-characterised test and appears to be quite 

 distinct from 1). amphora Leidy (1874), which was 

 afterwards recorded as D. urceolafa var. amphora 

 Leidy (1879) and includes forms which belong to 

 D. amphorali's Hopkinson (1908) ; from all these 

 D. lahiisa is distinguished by the recess around the 

 base of the neck of the test, and the wavy collar 

 following the undulations of he polygonal aperture. 



In Great Britain it is rare, being only recorded from 

 a single locality, and of the following dimensions : 

 length 265 p, ; greatest diameter 160 /u, ; aperture 

 65 /A. (Collected by H. E. Forrest from N.W. Anglesey.) 



6. Difflugia olliformis Lagerheim. 

 (Plate LX, figs. 8 and 9.) 



Difflugia olliformis 



LAGERHEIM in Geol. Foren. Stockholm Forli. XXIII (1901), pp. 512- 

 513, ff. 1-5. 



ZACHARIAS in Forschb. Plon. X (1903). pp. 286-287, pi. i, f. 20. 



AVERINTZEFF in Tmdui S.-Peterb. Obshch. XXXJ, n (1906), p. 213. 



SCHOUTEDEN in Ann. Biol. lacustre. I (1906). p. 348. 



WAILES in Jrn. Linn. Soc., Zool. XXXII (1913), p. 206, pi. xv, f. 12. 

 Difflugia subiequalis 1 



WAILES in Scott. Natur. 1912, p. 63 ; in Naturalist, 1913, pp. 145-146. 



Test of moderate size, broadly ellipsoidal, truncate ; 

 of a yellowish-brown or grey colour, chitinous, sparsely 



