93 
NEW BRITISH FRESH WATER ALGM. 
Mr. A. W. Bennett has recorded in the “ Journal of the Royal 
Microscopical Society ” for February, 1892, the species of Fresh 
Water Algse met with in a corner of South West Surrey, which 
contains a few new or interesting species. Amongst the latter 
are : — 
Trochiscia pachyderma ( Beinsch .) Hans. See Bennett Journ. B. M. S., 
t. ii., fig. 1. 
Fediastrum glanduliferum. Bennett Journ. B.M.S. , t. n., figs. 5-7. 
Coenobium elliptical, 300-400 ft, very dark green, solid, or with 
only very small intercellular spaces ; marginal cells usually 
pentagonal or hexagonal, with a small semi-circular incision in the 
external wall, two horned, each horn springing from about mid- 
way between the side wall and the incision in the external wail, 
quite hyaline, and sharply cut off from the endochrome of the cell, 
very slender capitate; marginal cells about 12*5 x 10 ft; horns 
about 15 ft long. The marginal cells somewhat resemble those of 
P. Ehrenbergii, but are not so deeply indented. The shape of the 
incision and the round knobs at the extremity of the horns dis- 
tinguish this pretty species from any other in the genus. 
Among water-weeds in pond. Frensham. 
Tetmemorus minutus. BBy. Conj., p. 74, t. v., f. 10. Bennett 
Journ. B. M. S., t. ii., f. 8-9. 
Length 45-50 ft, breadth 15-18 ft. 
Punchbowl, Hindhead. 
Micrasterias rotata, var. acutidentata. Benn. Journ. B. M. S., 
1892, t. ii., fig. 10. 
Terminal lobes of semi-cells bilobulate, with bidentate lobuli. 
Some of the lobuli of the lateral lobes tridentate, especially those 
at each extremity. Teeth of terminal lobes much sharper than in 
the normal form. 
Punchbowl, Hindhead. 
Euastrum inerme. Lund. 
Punchbowl, Hindhead. 
Cosmarium minutum. Benn. Journ. B. M. S., 1892, t. ii., fig. 11. 
Very minute. Length and breadth about 15-18 ft, semi-cells 
hexagonal ; ends quite straight and parallel, each side represent- 
ing a nearly equilateral triangle ; incision narrow and deep ; a 
large conspicuous pyrenoid in the middle of each semi-cell. 
In bog pools. 
Cosmarium Ungerianum. (Nag.), Arch. Benn. Journ. B. M. S., 
1892, t. II., figs. 12-13. 
Medium size. Outline nearly equilateral triangle. Length 
70-80 ft; breadth about 75 ft ; sides 42 ft; very nearly straight, 
or slightly convex, with rounded base ; ends 42 ft, quite straight, 
sinus moderately deep, triangular ; membrane rough with pearly 
