m
. .? ;û
OSCILLATORIA e u p e s t b i s .
Rock Oscillatoria.
C l a s s a n d O r d e r CRYPTOGAMIA ALGÆ, Lm«.—N a t . O r d . ALGÆ, Juss.
g e n e r i c c h a r a c t e r .
Fila muco communi matricali involuta, rigida, elastica, oscillantia, striis paraU
lelis transversis secta.—A g a r d h .
Filaments invested by a common mucous matrix, rigid, elastic, oscillating,
divided by parallel transverse striæ.
SPECIFIC character.
O s c i l la to r i a rupestris ; Jilis crassis, Jlexuosis, ceruginosis, limbo albo pelluci-
do, in stratum densum, sordide oeruginoso-viridum laxe intertexlis.
O. filaments thick, fiexuose, æruginose, with a white pellucid limb, loosely
interwoven, in a dense, dull æruginose-green stratum.
H ab. On the perpendicular sides of rocks, exposed occasionally to the trickling
of water. Pentland Hills. May.
Plant covering the face of the rock for several inches together, and, when
old, peeling off in rather large pieces. Fxternally it is mostly of a dull,
and often brownish-green colour, b u t within, more or less of a verdigris
green, differing in intensity in different parts : here and there gelatinous
and semitransparent. Filaments thick for their length, very
fiexuose, w ith a pellucid colourless limb, equal in breadth to the coloured,
striated portion, which is of a pale verdigris-green. Striæ rather indistinct,
not half as long as they are broad.
To the best of my knowledge, the present species of Oscillatoria
has not found a place in any publication. Its thick
and flexuose filaments, and the broad limb with which they
are provided, seem to characterise it sufficiently.
Fig. 1. 0. rupestris, natural size. Fig. 2. A portion remooed,
menls. Fig. 4. Portion o f a f lament;—magnified.
Fig. 3. Filaf
l