♦
H
airngiuous green, joints .shorter tlian broad ; sheaths thick,
golden brown, often encrusted with deposit of lime.
S iz e . Trichomes '008 mm., including sheath -01 mni.
Kirch. Alg. Schl. 225. Eabh. Alg. Eur. ii., 247.
Scytonema Jnliannm, W ittr. & Nordst. Alg. Exs., No. 273 a.
Drilosiphon muscicola, Kutz. Sp. 802.
Oscillaria cyanea, Hass. Alg. 248. Eng. F l.v ., 874. Harv.
Man. 163.
Conferva cyanea, Eng. Bot. ii., t. 2578.
Humida cyanea, Gray. Arr. i., 282.
On walls, stones, overrunning moss, &c.
Found on the walls of warm houses in the Eoyal Botanic Gardens at
Kew, and in Regent’s Park. This is evidently the Conferva cyanea of
English Botany found on damp walls in churches, &o, “ On tbe wall it
is conspicuous for its light sky-blue colonr, like some sort of
Under a high magnifier, and when moistened, it is fonnd to consist of
minute even simple entangled threads, coated with a frequently interrupted
covering of a dull glaucous green hue, under which the thread
itself appears of a lighter glaucous bluish colour, very even in thickness,
and surface consisting of scarcely distinguishable joints about as broad
as they are long.”—Smith.
Bornet and Thuret refer this to a variety of Scytonema Hoffmanni,
whilst Kirchner retains Meneghini’s specific name, which Thuret thinks
to belong to Scytonema ocellatum, Lyngbye.
Plate CVP. fig .l. a, trichomes X 400; b, portions of same X 400 ; c,
hormogones X 400.
S cytonema in te z iu p tum . Thw.
Intense bine-green, forming a stratum of the same colonr ;
sheath cellular, and furnished throughout its entire length with
numerous branched aud anastomosing rootlets ; trichomes distinctly
annulate, interrupted here aud there by heterocysts,
branches in pairs arising from the protruded triohome.
S iz e . Nowhere sta ted.
Rhizonema interruptum, Thwaites in Eng. Bot. ii. Supp., t.
2954.
Calothrix interi-upta, Carm. Eng. Fl. v., 8 6 8 . Harv. Man.
158.
Stigonema interruptum, Hass. Alg. 229, t. 69, f. 2.
In wet heathy places, coating mosses, &c.
We have seen no specimen of this, which is evidently a close ally of
S. einereum. The figure is reproduced from English Botany.
Plate CYl.fig. 2.
Scytonema interruptum, after the figure t. 2954,
English Botany.
Considerably magnified, presumably about 860 diam.
Genus 108. FFEETTAALLOONNEEMMAA.. Berlc. (1832.)
Trichomes enclosed in a very broad striate membranous
sheath, which forms a transparent layer, resembling a hyaline
wing.
Threads as in Scytonema, with the sheath very broad, forming a
transparent layer around the triohome.
F e ta lo n em a a la tum . Berk. Glean, t. 7, f. 2.
Forming a tlnn brown stratum. Trichomes small, a few
lines only in length, winged, obtuse, with numerous striæ, when
taken in conjunction with the wings or membranous expansions,
they are linear and plane. Each wing is about thrice the
breadth of the proper filament, of a white colour, somewhat
transparent, of a bright yellow next tlie filament, and exhibiting
nnder a favourable light a numerous series of transverse lines
or folds. Endochrome of the .central thread greenish and
septate.
S iz e . Trichomes -01 mm., with sheath from ‘05 to ’12 mm.
Hass. Alg. 288, t. 6 8 , f. 6 . Harv. Man. 168.
Arthrosiphon alatas, Eabh. Alg. Eur. ii., 265.
Arthrosiphon Grevillei, Kiitz, Sp. Alg. 311. Fischer Nost.
f. 1 0 .
Oscillatoria alata, Grev. So. Orypt. Flora, t. 222.
On rocks exposed to the trickling of water.
Plate QYII, Jiy. 1, Upper portion of trichome with sheath X 400
diam.
Genus 109. SY3VIPHY0SIFH0N. Kut%. (1843.)
Trichomes as in Scytonema. Filaments agglutinated in erect
wick-like bundles.
Symphyosiphon Hoffmanni. Kutz. Tab. Phyc. il., i. 43, /. 3.
Terrestrial, resembling a Symploca in habit. Tufts small,
ascending, dark brown ; trichomes simple, erect, loosely collected
in pointed fascicles, internally pale æruginous green,
sometimes interrupted, joints delicately granulose, inferior
cylindrical, tljiii, superior thicker and more or less swollen.
Sheath firm, broad, attenuated upwards, rarely acute, colourless,
or yellowish towards the base. Heterooysts intercalated,
globose, hyaline.
S iz e . Trichomes '01 mm. diam., with sheath •012-014 mm,
Scytonema Hoffmanni, Agardh Syst. p. 40. Eabb. Alg.
Eur. ii., 259.