DIEPLUGIA UEOEOLATA. 41 



(1906), pp. 344, 348; Thiebadd in Zool. Anzeig. XXX 

 (1906), p. 156 ; Thiebaud & Favee in Ann. Biol. Lacustre, 

 I, 1 (1906), p. 76 etc.; Hoogkneaad in Tydschr. Nederl. 

 Dierk. Ver. (2) X (1908), p. 407; Landacee inPr. Daven- 

 port Acad. Soi. IV, 10 (1908), p. 428. 



Difflugia pruteiformis sub-sp. mitriformis var. lagenifurmis 

 Wallich in Ann. Nat. Hist. (3) XIII (1864), p. 240, t. 

 xvi, tf. 15, 16. 



BMugia lageniformis Butsohli in Bronn's Thier-Eeichs, I, 

 1 (1880), t. iii, f. 8. 



Test ovoid, rotund, its crown obtusely and evenly 

 rounded, plain, or furnished vfith one or more short 

 bluntly-conical protuberances ; the neck short, con- 

 stricted above the wide circular mouth, which has an 



Pio. 56. — Typical form of Difflugia urceolata. Prom Eichmond Park, 

 Surrey, x about 180. 



expanded and slightly-recurved rim, its basal outline 

 being straight or convex. Body of the test, as well as 

 the expanded mouth, incrusted with quartzose sand- 

 grains and other opaque material. The plasma pluri- 

 nuclear, colourless ; the pseudopodia digitate, simple 

 or branching, generally numerous. 



Dimensions: Length 220-230 ju,; breadth 150-200 /a. 



In ponds and ditches, not common. Eichmond Park, 

 Surrey. Chipperfield, Herts {A. Emiand). Bowness, 

 Westmoreland {G. 8. West). Loch ISTess, Scotland 

 {D. J. Scourfield). 



D. urceolata is one of the largest of our native 

 Bifflugise. Though Avidely distributed in Europe and 

 America, it is not abundant in England. Both the 

 spined and spineless forms, however, occur in different 

 parts of this country. The test is opaque, and with- 



