Miciospoza iloccosa. (Ag.) Thuret. Reoh. t. 17, / . 4-7.
Articulations before division about twice as long as the
diameter, after division about equal, or a little shorter, slightly
constricted at the joints.
S iz e . Threads -015--017 mm. diam. (according to Kirschner
•0075--01 mm. diam.).
Kabh. Alg. Eur. iii,, 321. Thuret. Ann. Sci. Nat. 1850, t.
17, f. 4-5.
Conferva floccosa, Ag. Syst. p. 89. Kutz. Tab. iii., t. 43. f.
3. Eng. Fl. V., 351. Eng. Bot, ii., t. 2474. Harv. Man. 126.
Mack. Hib. 224. Gray Arr. i., 310. Kirsch. Alg. Schl. p. 79.
Lyngbya floccosa, Hass. Alg. 223, t. 60, f. 1-2. Jenner, Tunb.
Wells, 188.
Conferva fugacissima. Dill. Oonf. Supp. t. B.
In stagnant water.
Plate L l l l . fig. 3. a, J, portions o£ threads X 300; o, cells divided
across for the escape of zoogonidia X 300; d, zoogonidia.
Genus 59. CO N FE R V A . (Linn.) Link. (1820.)
Articulate threads simple, articulations cylindrical. Chlorophyllose
mass homogeneous or granulate, including starch
granules.
Vegetation by division in one direction.
Propagation unknown, (? by resting-spores which subsequently
produce zoogonidia).
Recently Wille has declared his belief in the universality of resting-
spores in the whole genus Conferva,* although it is hardly clear what
is his conception of the limits of the genus. In a new species which he
has described under the name of Conferva Wittrockii, he gives detailed
aooount of spore formation, which it is presumed may be accepted as a
type of what usually takes place.
“ The chlorophyllaceous contents contract, and heoome rounded. The
colouring m atter collects principally in the ends of the cells, so that the
substance in the middle appears almost colourless; but after the contraction
of the cell contents the chlorophyllaceous portions of the
protoplasm draw nearer together, until at last they coalesce and form a
round or elliptical body within the mother cell; they then begin to
surround themselves with a membrane, which later consists of two
distinct layers. The spores are generally set free by the filaments
resolving themselves into H shaped cells (in wliich the cell wall of each
cell has a transverse fissure in the middle of the transverse walls) ; the
spores then fall ont. Sometimes they escape by the cell walls becoming
converted into mucilage, their layers becoming gradually indistinguishable.
On first germinating, the size of the spores increases, as the
result of which the outer membrane bursts. The outer membrane
consists of two pieces with pointed ends, one being much larger than the
* Ofversigt at Kon. Vetensk Akad Forhaiidl. xxxviii (1881). “ Journal of Eoyal
Microscopical Society,” Dec., 1882, p. 836.
other, and covering it like the lid of a box Afterwards
expansion of the inner membrane, the smaller piece of J“®'“ '
brane gives way, an(il tbe inner membrane grows through the apeiture
thus formed in the form of a tube. The development was not followed
further, but the writer considers it probable that zoospores are first
formed from the resting spores.” . , i, „
In Conferva homiycina, var. minor, either smgle cells swell up into a
barrel shape, or here and there the contiguous ends of two neighbouring
cells assume a club-like form. I t is here that the largest part rf the
Chlorophyllaceous protoplasm accumulates, and after this the swollen
end is separated by a transverse wall from the longer narrow P“ * *®
mother-oell. The wall of the swollen part tffiokens later. The author
considers these cells to be resting-spores, although he was not aWe to
observe their germination. Conferva iombyoma var. genmna has similar
’’^Three^^-Ses of formation of resting-spores of Confervacece have been
observed—(1 ) by rejuvenescence, and the formation of a new membrane
r o r n d l o oL L tiJig contents;’(2) by the thickening of membrane
of the mother-cell; (3) by separation of a portion of the cell substance
to a swollen part of the mother-oell, and the thickening of the membrane
of this portion.
Conferva fo n tin a lis . Berlt. Glean, t. 14, /. 1.
Brffikt green, attached; articulations 6 to 10 times as long
as the diameter, slightly swollen, a little constricted at the
joints, starch granules single, scattered or seriate, cell-membrane
ra ther thick, homogeneous, when heated with sulphuric acid
swelling and distinctly lamellose.
Size. Threads •016--018 mm. diam.
Kutz. Tab. iii., t. 45, f. 4. Kabh. Alg. Eur. iii., 323. Kirsch.
Alg. Schl. p. 78.
Attached to grass, &c., in ditches.
“ I t covers rushes, grass, &c., with a short downy green coat, which is
very conspicuous in spring and sarnmevr—Berkeley.
Plate L l l l . fig. 6. Threads of C. fontinalis X 150. Fig. 7, por-
tions of thi’eads X 400.
C o n fe rv a t e n e r r im a . Kvtz. Tat. in ., t. 42,./. 1.
Usually pale green, articulations times as long as the
'^ ^ ^ zb!'^' Threads ‘OOSb-’OOd mm. diam. ( ‘OOS-'OOb mm.
Alg. Eur. iii., 322. Kirsch. Alg. Schl. p. 78.
I n fresh water, often mixed with other Algre.
Plate L JIL., fg , 5. Portions of threads of C. tenerrima X 400.
C o n fe rv a 'b om h y c in a . Ag. Syst. p. 83.
Yellowish green or green, soft, silky ; articulations oblong-
cylindrical, slightly constricted at the joints, before division
three times as long as the diameter, collapsing alternately when
dry.
ii