60 BRITISH FEESH WATER EHIZOPODA. 



oval, or, from a slight inflation immediately below the 

 constriction tapering down to the narrowed and trun- 

 cated mouth. Surface of the test moi-e or less thickly 

 incrusted Avith sand-grains and other material ; in some 

 examples comparatively smooth. 



Dimensions : Length 125-170 jn. 



Amongst sub-aquatic mosses at pond-sides, and in 

 wet Sphagnum in marshy places, not frequent. Pad- 

 gate near Warrington ; near Towyn, Merionethshire. 

 New Forest, Hants, and Llyn Idwal, N. Wales (6r. S. 

 West). Nant Francon, N. Wales (.7. Hopkinson). 



70 





71 





Pigs. 70 and 71. — Pontigulasia vas : 70, from Llyn Idwal, N. Wales, 

 X 100; 71, from the New Forest, Hants, x 60. From drawings by 

 G. S. West. 



Prof. Gr. S. West, in the Linnean Society's ' Journal,' 

 vol. xxviii (Zool.), p. 318, records the dimensions of 

 examples found in the New Forest as 470 ju, in length 

 and 380 /a in breadth, and those from Llyn Idwal, he 

 states, were approximately of the same size. These 

 dimensions very much exceed those given by Penard 

 for the species. But it is a variable one. The example 

 figured on Plate XXIII (fig. 1) from Padgate, was 

 remarkably fine and well-formed, but whilst the con- 

 striction was deep and clearly defined, the form differed 

 from Penard's figure of " P. spectahilis " in having the 

 sides of the neck (from the constriction downwards to 

 the mouth) evenly convex instead of straight. There 



