6 
Transactions of the Society. 
OsCILLATORIACEiE. 
Oscillatoria * tenerrima Ktz. 
,, limosa Ag. 
„ princeps Vauch. 
„ Frolichii Ktz. 
„ tenuis Ag. 
ScYTONEMACEiE. 
Scytonema figuratum Ag. 
Stigonema minutum Hass. 
Rivulariacea:. 
Gloeotrickia Pisum Thur. 
In the large pond at Frensham ( probably tbe same locality as that 
referred to in Cooke’s Fresbw. Algas, p. 279), I found several 
specimens of a very interesting organism which is no doubt tbe Iiivu- 
laria ecliinulata of Engl. Bot., t. 1378 (11. echinata in Cooke), identi- 
fied by Bornet and Flabault with Gloeotrichia Pisum Tbur. It was 
found only in very small quantities, in tbe form of radiating olive- 
green clusters of filaments, attached to Anacliaris and Utricularia, 
immersed in gelatin. Each filament is inclosed in a distinct colour- 
less sheatb, often extended considerably beyond tbe endocbrome, and 
very narrow at tbe extremity. Tbe pseudocysts are subquadrate, 
about as broad as long at tbe base of tbe filament, narrowing ratber 
rapidly in tbe upper part, and towards tbe apex several times longer 
than broad. At tbe base of eacb filament is a colourless spherical 
keterocyst, with a bright spot at its distal end. On a second visit no 
further specimens could be obtained. 
Nostocacea:. 
Nostoc piscinale Ktz. 
„ opalinum Benn. 
(N. hyalinum miki, Journ. R. Micr. Soc., 1887, t. 1, f. 2, non 
Roem.) Precisely resembling the form previously gathered by me 
in Westmoreland and in Cornwall, except that tbe frond was quite 
spherical. 
Anabsena flos-aquae Ktz. 
„ variabilis Ktz. 
„ oscillarioides Bor. 
„ „ /3 elongata (Sphcerozyga elastica Rifs.). 
Aphanizomenon flos-aqufe Rifs. 
* Gomont has shown (Journ. de Bot., Aug. 1891) that Oscillatoria, and not 
Oscillaria, is the older name. 
