DIFPLTJGIA BAOILLARIARUM. 



29 



In bog-pools in Delamere Forest, Dunliam, and else- 

 wliere in Cheshire ; freqnent in North Wales. 



This variety comprehends a number of forms, all of 

 which possess the characters specified, with, however, 

 some modifications. Those incrusted with sand-grains, 

 some of which are figured by Penard (' Faune Ehiz. 

 Leman,' p. 237) may belong to the var. SoloweUldi. 

 It is desirable to confine var. elegans to those which 

 have a chitinous test, are diatom-covered, and more or 



Pigs. 4S-50. — Varieties of Difflugia bacillariarum. Figf. 48. — Var. 

 elegans. After Penard (as Difflugia elegans) ' Faune Ehiz. Leman,' 

 p. 237, fig. I. Fig. 49. —Var. teres. After Penar4 (as D. elegans Far. 

 teres) ' Sarc. grands Lacs,' p. 16. Fig. 50. — Var. Solowetukii. After 

 Mereschkowsky (as D. Solowetzlcii) in ' Arch. mikr. Anat.' XVI, t. x, 

 f.'lY. All X about 280. 



less transparent. Wherever the organism occurs it is 

 usually plentiful, and individuals inhabiting the same 

 water, and even the same drop, exhibit a remarkable 

 range of forms. 



10. [?] Difflugia curvicaulis Penard. 



(Plate XIX, fig. 8.) 



Difflugia curvicaulis Penakd in Rev. Suisse Zool. VII, 1 

 (1899), p. 36, t. iii, ff. 2-6; Faune Ehiz. Leman (1902), 

 p. 242, ff. 1-4 (p. 243) ; and Sarc. grands Lacs (1905), 

 p. 16, f. (p. 17) ; Letakdee in Acta. Soc. Fauna Fenn. 

 XX (1901), 8, p. 12, f. (p. 13) ; AvEEiNTZEV in Trudui 



