330 MR. G. S. WEST ON SOME BRITISH 
Gen. CypHopERrtia, Schlumberger. 
47. CYPHODERIA AMPULLA, Leidy, in Proc. Acad. Nat. Set. 
Philad. 1878, p. 1738; Freshw. Rhiz. N. Amer. 1879, p. 202, 
t. xxxiv. ff. 1-16.—Difflugia ampulla, Hhrenb. 1840; Abhandl. 
Akad. Wiss. 1871, t.i1.f.11. Cyphoderia margaritacea, Schlum- 
berger, in Ann. Sci. Nat. 1845, ii. p. 255; Hertwig f Lesser, in 
Archiv fiir mikr. Anat. 1874, x. Suppl. p. 182. Euglypha curvata, 
Perty. HE. margaritacea, Wallich. Cyphoderia margaritacea, 
var. major, Penard. 
General and abundant. The largest specimens observed were 
equal in size to those described by Penard as var. major, and 
were obtained from Stavely Dam, near Knaresborough, W. York- 
shire. Length up to 165,; breadth 66. It was obtained at 
over 3000 ft. elevation on Snowdon, N. Wales. 
The form with the prominent mamillate process at the fundus 
was noticed from Wicken Fen, Cambs., and from Lough Neagh, 
Ireland. 
From Llyn Idwal, N. Wales, many active animals were noticed 
in which the body-protoplasm had retreated from the thick end 
of the shell, leaving a large space, but no strands of protoplasm 
stretched across this space from the body-protoplasm to the 
shell as in Arcellas and Hyalosphenias. 
From Bowness, Westmoreland, numerous small specimens 
were observed with an apparently homogeneous, deep-brown shell, 
which was asperulate on its outer surface. The neck was also 
more pronounced and bent than in any other specimens I have 
seen. Length of shell 81-87 «; breadth 28-81 u. 
Fam. GROMIINA. 
Gen. PseupopiFFiueta, Schlumberger. 
48. PsEUDODIFFLUGIA G@RaACcILIS, Schlumberger, in Ann. Set. 
Nat. 1845, i. p. 254; Letdy, Freshw. Rhiz. N. Amer. 1879, 
p. 198, t. xxxiu. ff. 18-28.—Pleurophrys spherica, Clap. et Lachm. 
1859. Pleurophrys? ampbitrematoides, Archer. 
Somewhat scarce and liable to be overlooked. 
Capel Curig, N. Wales, amongst Sphagnum. Also near the 
outlet of Llyn Bochlwyd, N. Wales. 
Gen. Pampuaatus, Bailey. 
49, PaMpHacus HyaLinus, Leidy, Freshw. Rhiz. N. Amer. 
1879, p. 194, t. xxxiii. ff. 18-17.—Arcella? hyalina, Hhrenb. 
