CHETOPHORACEA, 189 
Propagation by oospores or zoogonidia, the latter formed by 
division (4-16) of the cell contents, each zoospore furnished with 
a red parietal spot and four vibratile cilia, 
Stigeoclonium thermale. Braun in Kutz. Spec. p. 352. 
Bright green, very much branched in a fasciculate manner, 
somewhat creeping at the base, filaments and branches attenu- 
ated upwards to the cuspidate apex, branchlets for the most 
part alternate, rather remote, nearly erect or somewhat diver- 
gent, setiform, joints variable in length, at the base of the 
filaments equal or twice as long as the diameter, becoming 
turgid, in the upper part of the branchlets 8-5 times as long as 
the diameter ; chlorophyllose bands broad, sometimes effused. 
Sizz. Cells 012 mm, 
Rabh. Alg. Eur. iii., 876. Kutz. Tab. Phye. iii., t. 2, f. 4. 
Draparnaldia elongata, Hass. Alg. 128, t. 10, f. 8. Ann. 
Nat. Hist. Aug. 1842, xi, p.4. 
In thermal springs, &e. 
Hassall found this species on one occasion growing in a horse-trough. 
It is sometimes mixed with other alge in ditches. ~ 
Plate LXXIIL. fig. 2. Filament of Stigeoclonium thermale with 
zoogonidia X 400 diam. 
Stigeoclonium tenue. Ag. Syst. 57. 
Bright green, lubricous ; filaments a little branched, branches 
nearly simple, cells equal or 2-3 times as long as their diameter, 
more or less distinctly constricted; chlorophylluse bands 
narrow ; branchlets scattered, shortened, nearly erect, subulate; 
cells at the base longer than broad, abbreviated towards the 
apex. 
Size. Cells ‘01 mm. diam. 
Kutz. Tab. Phye. iii, t. 8, f.1. Rabh, Alg. Eur. iii, 377. 
Kirch. Alg. Schles. p. 68. 
Draparnaldia tenuis, Eng. Fl.v., 888. Eng. Bot. it, p. 199. 
Harv. Man. 122. Mack. Hib. 222. Hass. Alg. 123, t. 11, 
f. 2. 5 
Conferva lubrica, Dillw. Conf. t. 57. Grev. Fl. Ed. 318. 
Hook. Fl. Scot. ii., 82. Gray Arr. i, 303. 
Conferva exigua, Dillw. Conf, t. 2 (young), 
In streams and ditches. 
“ At first the filaments are enclosed, in the manner of a Chetophora, 
in a common, somewhat definite gelatine; afterwards, on its bursting, 
they issue from it like a Conferva, but are at all times very gelatinous.” 
—Harvey. 
Plate LXXIII. fig. 3. Filament of Stigeoclonium tenue x 400 diam. 
Ge 
