334 MR. G. S. WEST ON SOME BRITISH 
chromatophore and surrounding protoplasm of the vegetable cell 
had been absorbed by the Vampyrella. 
It has been stated by some authors that Vampyrella does not 
perforate the cells of Spirogyra and other filamentous alge on 
which it feeds, but attacks them and devours their contents by 
breaking the filaments at the joints. It is possible that it does 
so sometimes, but Cienkowski’s original observation of the per- 
foration of the cells of Spirogyra by this animal is, however, 
amply confirmed by the attacks I observed V. lateritia to make 
on the cells of Mougeotia, a plant which breaks at the junction 
of the cells much more readily than Spirogyra. 
55. VAMPYRELLA PEDATA, Klein; Blochmann, Die mtkros. 
Thierwelt des Stisswass., 1. Protozoa, Hamburg, 1895, p. 22.— 
Hyalodiscus rubicundus, Hertwig & Lesser, in Archiv fur mikr. 
Anat. 1874, x. Suppl. p. 49, t. ii. f.5. Plakopus ruber, & L. 
Schulze, in Archiv fur mikr. Anat. 1875, xi. p. 348, t. xix. 
ff. 9-16. 
In the lakes at Capel Curig, and in Llyn-y-cwm-ffynon, 
N. Wales. ‘Diameter of encysted stage 53-67 p. 
The animals observed were subspherical or ovoidal in form, 
with the endoplasm filled with small granules of a bright red 
colour. They had previously been gorging themselves with food, 
as they were filled with large numbers of small Desmids, the 
contents of which had also become of the same red colour, 
I was at first inclined to regard them as forms of Hyalodiscus 
rubicundus, but I think there is no doubt that the form described 
and figured by Hertwig & Lesser is merely a stage of Vampyrella 
pedata. The red colour of the Welsh examples was identical 
with the red colour observed in Vampyrella lateritia. 
Class HELIOZOA. 
Order APHROTHORACA. 
Gen. ActinopHeys, Hhrenb. 
56. ActrNnopHrys Son, Ehrenb. in Abhand. Akad. Wiss. 
Berlin, 1830, pp. 42 ete. t. u. f. 4; Infus. 1838, p. 808, t. xxxi. 
f£. vi; Wallich, in Ann. Mag. Nat. Hist. 1863, xi. p. 446, t. x. f.4; 
Leidy, Freshw. Rhiz. N. Amer. 1879, p. 235, t. xl.—Trichoda Sol, 
Miller. Actinophrys difformis, Lhrenb. 
