FRESHWATER RHIZOPODS AND HELIOZOA. 331 
1838. Gromia hyalina, Schlumberger, 1845. Lecythium hya- 
linum, Hertwig & Lesser, in Archiv fiir mikr. Anat. 1874, x. 
Suppl. p..177, t.-im. f. 8. 
Not uncommon in ponds and lakes. Observed most abun- 
dantly from ponds, Cirencester, Gloucestershire, among Potamo- 
getons. Also abundant among TIsoétes, Llyn Idwal, N. Wales. 
Diam. 32-38 p. 
50. PampHaaus curvus, Leidy, J. c. p.196, t. xxxui. ff. 11, 12. 
The specimens were obtained from amongst mosses on wet 
rocks at over 3000 ft. elevation on Snowdon, N. Wales. They 
agreed very well with the animals described by Leidy, but were 
somewhat larger. Length 59-76; greatest breadth 32-386 p. 
CEl29. tie h272) 
The vertical aspect of the animal was circular, aiid the pseudo- 
pedia, which were much branched, exhibited somewhat active 
movements. The animals were all boiling upon a small species 
of Nitzschia, individuals being observed in which the whole body, 
inside the thin, hyaline shell, was packed with the valves of this 
Diatom. 
Gen. GromiA, Dujardin. 
51. GROMIA STAGNALIS, sp.n. (PI. 29. fig. 28.) 
Body small, perfectly spherical, usually green in colour- 
Shell chitinoid, spherical, colourless or straw-coloured, very thin 
and transparent, smooth on its external surface. Mouth small, 
not readily visible. A large amount of protoplasm is exuded 
from the mouth, flowing all over the exterior of the shell, and 
giving rise to numerous, divergent and anastomosing pseudopodia. 
Nucleus small, often not visible, situated in the region away from 
the mouth. 
Diameter of body 28-82 yp. 
Among Lemna minor in stagnant ditches, near Brigg, Lincoln- 
shire. 
This beautiful Rhizopod occurred in abundaace in the sediment 
collected by washing and squeezing Lemna minor and a few 
species of filamentous alez. The only other freshwater species 
of Gromiaare G. fluviatilis, Dujardin (in Ann. Sci. Nat. sér. 2, 
tom. viii., Zool. pp. 310-313), and G. terricola, Leidy (in Proce. 
Acad. Nat. Sci. Philad. 1874, p. 88; Freshw. RKhiz. N. Amer. 
1879, p. 277, t. xlvii. ff. 1-4). From both of these species 
G. stagnalis is readily distinguished by its small size, green 
