Ser. CHLOROSPERMEA. Fam. Oscillatoriea. 
Prats CV. A. 
Gen. Cuar. Filaments lying in a mucous matrix, rigid, simple, acicular, 
vividly oscillating. Yue continuous ; endocrome green, densely annu- 
lated with close, parallel, transverse stria.—Oscrtiatoria, (Vauch.), 
from the motion observed in the filaments, which resembles the osci/- 
lations of a pendulum. 
Oscritatorra Jittoralis, Carm. Stratum of a vividly eruginous green 
colour ; filaments thick, dark green, variously curved ; strize conspl- 
cuous, close-set. 
OscriLatorIA littoralis, Carm. Alg. Appin. ined. Harv. in Hook. Brit. Fl. 
vol. ii. p. 375. Harv. Man. p. 165. 
Has. In pools, along the muddy sea shore, flooded by Spring tides. 
Appin, Capt. Carmichael. 
Descr. Stratum exceedingly thin, slimy, bullated by the extrication of air bubbles, 
of a dark green colour, spreading to an indefinite extent over the muddy 
bottom of the pool. Filaments 1-2 lines long, much thicker than those of 
O. nigra, straight or slightly curved, radiating very irregularly, and gene- 
rally in twisted bundles. S¢riz strongly marked, at intervals of about one 
third the diameter of the filament ”. Carm. lc. 
Of this I have only seen Capt. Carmichael’s specimens, from 
one of which the figure is taken. I find the filaments curved 
and twining together; the striz very dense, and the mass of 
endochrome divided at uncertain intervals into portions, which 
probably break off eventually and become new filaments. 
A, Fig. 1. OscILLaATORIA LITTORALIS, part of a stratum :—of the natural size. 
2. Filaments :—highly magnified. 
Puate CV. B. 
OSCILLATORIA SPIRALIS, Carm. 
OsciLLatoriA spiralis; stratum membranaceous, or coriaceous, «eruginous 
or blackish-green ; without much lubricity ; filaments slender, spirally 
twisted, densely interwoven, radiating in all directions. 
OscriLaTortia spiralis, Carm. Alg. Appin. ined. Harv. in Hook. Br. Fl. vol. 2. 
p. 377. Harv. Man. p. 167. 
OscILLATORIA subsalsa, Harv. l.c. p. 376. Harv. Man. p. 165. 
SPIRILLUM rupestre, Hass. Freshw. Aly. p. 277. t. 75. f. 6. 
Has. On rocks by the sea-side, above and between tide marks. At Appin 
by rocks where birds are in the habit of resting, Capt. Carmichael. 
