213 
damp houses, and is to be well seen in the Nepenthes house and 
in many of the pits. Its appearance is very curious, the colour 
being very like that of a Mucor. e filaments are encrusted 
with a deposit of lime, giving them a black, opaque appearance 
under the microscope. 
Symphyosiphon, Kiitz., 1843. 
S. Hoffmanni, Kiitz. Tab. Phyc., ii., t. 43, f. 3. Forming m 
tufted growths on rocks in the Nepen nthes house, March, 1902 ; 
walls in pit, April, 1902 ; amongst moss in tropical fern Rodi. 
August, 1902 
Tolypothrix, Kütz., 1843. 
T. aegagropila, Kütz. Tab. Phyc., i, t. 32, f. 3. Forming 
numerous brownish circular patches on walls in many of the 
warmer pits, October, 1902. 
V gmaea, Kiitz. Amongst other blue-green Algae on 
wet stones in Victoria regia house, September, 1902. 
Var. muscicola, Kiitz. Intermingled with Gloeocapsa cald- 
ariorum and forming a blackish-green layer on the walls in the 
Nepenthes house, March, 1902; also on rocks in the same house. 
Var. Kewensis, var.nov. Filaments only slightly branched ; 
no branch beneath most of the heterocysts. Heterocysts single, 
ow i 
slightly granular, of the same size as the neighbouring cells. 
HM cells a little shorter or longer than broad, with blue- 
n to green, granular contents; filaments at some 
distinctly, at others indistinctly, septate. Sheaths colourless 
with thickish walls, 13 » in diameter; cells 10-12 » in diame- 
ter; heterocysts have the same diameter. When still occu- 
pie ed by the filaments the sheaths are difficult to distinguish. 
p 
in the degree of branching, For umerous, small, blue- 
green tufts on mosses in the eise en house, June, 1902, 
(the eolour somewhat resembles that of d cinereum). 
T. tenuis, Ktz. Phyc. Gen., 228, n. 4. On walls in palm house, 
March, 1902 ; on 2m in stove (No. 9), September, 1902 ; forming 
a dark blue-green ratum on the ledges in the pits, attached to the 
Orchid houses, oes a 1902. 
T. Wimm — at ae pk Schl. 228. Forms a shining 
blackish ence on a ledge one of the pits attached to the 
Orchid houses, irai Pie 1902 forms a thin, dark olive stratum 
on the stone floor of Aroid Rouse (No. 1), September, 1902. New 
for the British Isles. 
5. CALOTHRICHACEA EE. 
cpi Roth., 1824. 
R. echinulata, Berk. Engl. Bot. On the stone floor of the palm 
house, and on the sides of the tanks in the water-lily house, 
September, 
