DIPLOCHLAMYS. 81 
vesting the animal and provided with an elastic 
aperture; the outer envelope consisting of loosely- 
aggregated particles of silicious, earthy, or vegetable 
materials, the aperture large, partially or completely 
closed by the inner membrane ; plasma clear, granular, 
containing various inclusions consisting usually of 
food-particles, excretory granules, and occasionally 
crystals; nuclei varying in number from one to one 
hundred or more; contractile vesicles usually present ; 
pseudopodia few, short, digitate or pomted. Multi- 
plication takes place by division. 
For a detailed account of this genus, Penard 
(‘Archiv. f. Protist.,’ 1909) should be consulted ; five 
species are described, three of which have been 
recorded from Great Britain. VD. fragilis Penard and 
D. gruberi Penard have not, up till now, been recorded. 
SYNOPSIS OF THE British SvEcrEs. 
Test cup-shaped, dark grey in colour; nuclei varying from 
one to twenty in number. (1) D. leidyi. 
Test approximately hemispherical, about 45 u in diameter ; 
nucleus single, 7°5-10 yw in diameter. (2) D. timida. 
Test approximately hemispherical, about 100 u in diameter ; 
nuclei usually over 100 in number and 3:5 w in diameter. 
(3) D. vestita. 
1. Diplochlamys leidyi Greeff. 
(D. fragilis, Plate LX, fig. 5.) 
Diplochlamys leidyi 
GREEFF in Sitzb. Ges. nat. Marburg, ITI (1888), pp. 104-106. 
AVERINTZEFF in- Trudui S.-Peterb. Obsheh, XXXVI, 11 (1906), 
. 165. 
Gen on eenat in Ann. Biol. lacustre, I, 3 (1906), p. 338. 
PrwnaRD in Arch. Protist. XVII, 2 (1909), pp. 270-272, 274, 275; in 
Brit. Antarct. Exped. I, Biology, 6 (1911), pp. 220, 232. 
Waites & PenarpD in Proc. R. Irish Acad. XXXI, txv (1911), 
pp. 9, 16. 
Test hemispherical or cup-shaped, dark grey in 
colour, the exterior covered with fine silicious grains 
and earthy particles; the inner membrane clearly 
