336 MR. G. S WEST ON SOME BRITISH 
in A. subalpina quite a prominent feature. It is subspherical, 
situated more or less in the centre of the body, and exhibits a 
delicately dotted appearance, probably due to numerous fine 
granules. 
The contractile vacuole is relatively large and is situated at one 
side of the body. It commonly projects somewhat from the 
outer surface of the body, and but for this protuberance the 
animal presents an even edge all round. 
The habitat of A. subalpina is somewhat remarkable, the 
animals occurring amongst mosses on the vertical face of dripping 
rocks, and also at a considerable elevation above sea-level. I have 
never yet found A. Sol except in still water. 
The dumbbell-like form of the animal (which I figure to 
illustrate the species—PI. 30. fig. 836) might be considered merely 
as a case of fission, or as one stage in the conjugation of a pair 
of individua!s. When found it was in the stage figured. It was 
watched for some hours, and it ultimately separated into two 
individuals; but, as these individuals were normal and did not 
undergo any further changes so long as they were under observa- 
tion, I am inclined to regard it merely as ordinary fission. 
Gen. AcTINOsPrmRIUM, Stein. 
58. AcTINospHzRIUM Ercunornu, Stein, Sitzungsb. bohm. 
Akad. Wiss. 1857, p. 41; Hertwig & Lesser, in Archiv fir 
mikr. Anat. 1874, x. Suppl. p. 176, t. v. f£.1; Letdy, Freshw. 
Rhiz. N. Amer. 1879, p. 259, t. xliiActinophrys Hichhornii, 
Ehrenb. 1840. 
Widely distributed in still water, but not so abundant as 
Actinophrys Sol. 
Order CHLAMYDOPHORA. 
Gen. HELiopuRys, Greeff. 
59. HELIOPHRYS VARIANS, nob.—Heterophrys varians, Schulze, 
in Archiv fiir mikr. Anat. 1874, x. p. 386, t. xxvi. ff. 2-5. 
Heliophrys variabilis, Greeff, ibid. 1875, xi. p. 28, ff. 20-23. 
In ditches, near Brigg, Lincolnshire. Diameter of body 25 p. 
There can be little doubt that Heterophrys varians, Schulze, 
and Heliophrys variabilis are forms of the same animal. The 
general body of the animal has in each ease the same structure, 
