PLATE XIX. 



FIGS. 



1, 2. Difflugia oblonga var. lacustris (Penard) Cash. (p. 12) 

 Typical forms from ponds at Northenden, Cheshire. 

 x 280. 

 3, 4. D. oblonga Ehrenb. (p. 4) Two forms of test in 



Sphagnum from Dunham, Cheshire. x 280. 

 5-7. D. petricola Cash. (p. 18) Figs. 5, 6. Lateral and 

 oral views of an empty test. Fig. 7. A peculiar 

 double test formed of aggregated sand-grains, with 

 two apertures. Dunham Marsh, x 280. 

 8. (?) D. curvicaulis Penard. (p. 29) In Sphagnum from 



Criccieth, August, 1904. x 280. 



9-11. D. lanceolata Penard. (p. 31) Examples showing 

 variation in form and size ; from Cheshire ponds. 

 x 280. 



12, 13. D. brevicolla Cash. (p. 38) Fig. 12. Oral view of 

 an empty test. Fig. 13. Two individuals in conju- 

 gation. From a peat-moss near Warrington. x 280. 

 14-20. D. constricta (Ehrenb.) Leidy. (p. 54) Various forms 

 more or less common in ponds and amongst Sphag- 

 num. Fig. 17. A spined form. From Dunham. 

 Fig. 18. A large form in Sphagnum from Tan-y- 

 Bwlch, June, 1908. Figs. 19, 20. Lateral and front 

 views of an empty test. Dunham, 1904. x from 

 300 to 360. 



