The English flora - SeaweedAfrica

366 ALGM CONFERVCIDE.E. .Calothrix.
elongating into branches. Can this be the origin of the oppositional
branches of the Calothrices?— Conferva mirabilis ; E. Bot. t. 2219, (not
of Dillw.) which Agardh in his last work makes a variety of Sphacelaria
cirrhosa, I can refer with confidence to the present, having examined
Miss Hutchins' specimens, from which Sowerby's figure was taken.
Much confusion has arisen by Sir J. E/ Smith's stating, that the plant
was gathered " in Bantry bay," instead of " near Bantry." The specimens
are parasitical on an Orthot/ichum (probably O. rivulare), and
their fresh-water locality is thus clearly proved.
5. S. cirrhosum, Carm. (tufted Scytonema); "tufts widely
spreading, filaments floating in bundles spuriously" (?) " branched,
branches beset with fragments towards the top." Carm.
MSS. cum ic.
Borders of lakes at Lismore island, Capt. Carmichael.—'« It occurs in
continuous fleeces, parallel to the water's edge, of a deep chestnut
colour when lying flat, dark-olive when floating. The fleeces are made
up of small contiguous fasciculi of interlaced filaments. The filaments
are from half an inch to an inch in length, simple or spuriously (?) branched,
and prolonged by the successive adhesion of portions, seemingly of
broken filaments, which at length coalesce and form a knot at the point
of adhesion. The transverse spires are close and conspicuous." Carm.
MSS. I rather suspect that what Carmichael terms spurious branches,
have the same origin as the branches of S. myochrous, of which this
species is perhaps a variety, though the habit is very different. -
6. S. contextum, Carm. (interwoven Scytonema); " filaments
mostly simple interwoven into a tough olivaceous stratum which
turns to a dull-green in drying." Carm. MSS.
On the moist earth, Appin, Capt. Carmichael. Rocks at the foot of Turk
Mountain, Killarney, IV. H. Harvey.— " This species occurs in a thin,
closely-matted, blackish fleece, of indeterminate extent. Filaments 2—
lines in length, simple or rarely furnished with one or two branches,"
(which are occasionally geminate as in S. myochrous,) " interwoven into
an almost inextricable stratum. Sporidia, when visible, which rarely
happens, globular and rather distant. Besides the comparative shortness
of the filaments, and the more intimate contexture of the stratum,
this species differs from S. myochrous in becoming, when dry, of a light
greyish-green colour, instead of black." Carm. MSS.
7. S. byssoideum, Ag. (downy Scytonema); filaments minute
erect simple flexuose fasciculate forming an unequal blackish
crust.—Ag. Syst. Alg. p. 39.
On the trunk of a living Elm, at Oundle, Northampton, Rev. M. S.
Berkeley.—This forms a very thin, effused, blackish, velvetty crust. Filaments
exceedingly short, olivaceous, equal, very obtuse, erect, flexuose,
often joined together laterally into little compressed tooth-like fascicles.
Annuli close and evident.
73. Calothrix. Ag. Calothrix.
Filaments destitute of a mucous layer, erect, tufted or fasciculate,
fixed at the base, somewhat rigid, without oscillation. Tube
continuous ; endoclirome green, densely annulated, at length dis-
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