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sponge, with its surface beset by erect branches which give it a very
bristly appearance. In this state it is well known to botanists as the
C. amphibia of all modern authors. Its hue is of a bright green,
becoming ash-coloured with age. The root I have not been able to discover,
and the entangled mode of its growth renders it impossible to
ascertain the length of the filaments. These are repeatedly divided with
distinot patent branches, which, as before mentioned, when the plant
grows in shallow water, so that some of them are exposed to the air, send
out patent ramuli, of a stunted growth, from being out of their proper
element, which by their ereotuess give the plant its bristly appearance;
yet at the same time, if whilst in this state the waters rise so as to overflow
the plant, jheir length is gradually increased, and losing their erect
position they yield to the current, and become the Ceramium ctvspitosum,
of Both ; and after having thus changed, if by the subsidence of the
waters the surface is again exposed to the air, the filaments, of course
disposed horizontally, give the plant a bristly appearance by again throwing
out erect patent ramuli.”
var. o z n ith o c e p h a la . Hassall Alg. t. 6, /. 4.
In dirty green tufts, densely imbricated, and becoming paler.
Tballus loosely branched. Oogonia solitary, or in pairs, oval-
oblong, obliquely rostrate, beaks truncate, antheridia cylindrio-
subulate, incurved, interposed, usually exceeding in length the
diameter of the oogonia.
Vaucheria ornilhocephala, Eng. PI. v,, 320. Harv. Man.
148. Hook. PI. Soot, ii., 93. Eng. Bot. ii„ p. 195. Grev.
Alg. Britt. 193. Grev. El. Ed. 306. FL Devon, ii., 56.
Gray Arr. i., 291.
Conferva vesicata, Dillw. Conf. t. 74.
In stagnant or slow-flowing water.
var. r e p e n s . Hassall Alg. t. 6, /. 7. Ann. Nat. Hist, xi., 430.
Terrestrial. Oogonia single, sessile, oblong or ovate, shortly
rostellate, mouth lateral, truncate. Antheridia solitary, next
tbe oogonium, cylindric-olavate, erect, inclined or curved,
scarcely longer than the oogonium.
On tbe naked ground.
I t is on Vaucheria sessilis that Sir J. E. Smith says are found th
“ Vesicles of the nature of galls, perhaps, inhabited by Muller’s Cyclops
lupvla,” figured on plate 2419 of the second edition of English Botany.
Hassall states that the species is V. geminata, but this is accounted for
by the belief which was current in those days that V. geminata was the
summer form of V. sessilis.—See Eng. Bot. ed. ii., p. 125.
Plate XLVI., figs. 1 to 20. Impregnation of Vaucheria sessilis, after
Pringsheim x 200.
Plate X L V in ., fig. 1 , part of thread, with sexual organs, of V. sessilis.
Fig. 2, oogonia and antheridia X 200. Pig. 3, oogonia and antheridium
of the variety caspitosa X SOO. Fig. 4, oogonia and antheridium of the
terrestrial variety repens x 200. Pig. 5, threads bearing sporangia at the
tips slightly magnified.
6 . V a u c h e ria g em in a ta . (Vauch.) Walz. Jahi'b. p. 147, f. 12,/. 7-11.
Dark or dull green, in dense intricate tufts. Thallus capillary,
tougb, dichotomous. Oogonia two (rarely 1 or 3),
ovate or obovate, opposite, distinctly pedunculate. Antheridia
intermediate, subulate, more or less recurved. Mature oospore
spotted with brown, sporoderm colourless, composed of three
strata. Sporangia on the same or a proper tballus, broadly
cup-sbaped, truncate, and angularly horned.
S iz e . Oospore •11-T2 x •18-'19 mm.
DCand. FL Pr. ii., 62. Hass. Alg. t. 3, f. 1. Cleve Vauoh.
p. 6, f. 4. Kirsch. Alg. Schl. p. 88. Kutz. Tab. Pbyo. vi.,
t. 59, f. 3. Eng. FL V., 320. Harv. Man. 148. Eng. Bot.
i., t. 1766, ii., t. 2420. Grev. Alg. Britt, p. 193, t. 19.
Purton Mid. FL ii., 611. Jobnst. FL Berw. ii., 252. Grev.
FL Ed. 306. FL Devon, ii., 56. Gray Arr. i., 291.
Ectospernia geminata, Vauoh. Conf. 29, t. 2, f. 5.
Vaucheria Dillwijni, Rabh. Alg. Sachs. No. 1078.
To this species we also refer tbe following as synonyms,
although usually referred to V. sessilis:—
Vaucheria ovoidea, Hass. Alg. 57, t. 5, f. 3.
Vaucheria ovata. Gray Arr. i., 289.
Ectosperma ovoidea, Huds. FL Aug. 954. Hook. FL Soot.
979. With . Arr. iv., 129.
In ponds and ditches.
var. f ra c em o sa .
Oogonia shortly pedunculate, 3 to 5 or more aggregated
in a corymbose manner. Antheridia single, scarcely longer
than tbe oogonia.
S iz e . Oospore ’Ob-’OS x '075-’08 mm.
Vaucheria racemosa, Eng. Bot. ii., 126. Grev. Alg. Britt.
195. Harv. Man. 149. Grev. FL Ed. 806. Gray Arr. i.,
292. Hass. Alg. 56, t. 3, f. 2.
We have reproduced Hassall’s figure of this form in which the antheridium
is considerably longer than the oogonia. Vaucher says, “ This
species is one of the most common, and is found in nearly all ditches,
principally in the spring. I t is loaded with little bouquets manifest to
the unassisted sight, and which with the microscope seem to be formed of
a common peduncle, subdivided into pedicels, each of which carries on
its summit a spherical body in every way resembling the grains of other
ectosperms, but nearly half as small again. In the middle of this
bouquet is the horn, which, without doubt, performs the function of a
male flower, and which is here but a prolongation of the peduncle. The
number of grains varies from 5 to 7, but commonly 4 are met with.”
I t is of this species that Hassall says, “ It is most frequently infested
with the curious parasite Cyclops lupula of Muller, which occasions the
growth on the filaments of such extraordinary-looking appendages, in
the midst of which the parasite resides.” This parasite, whatever it may
be was the subject of a communication by Mr. A. Lister to the Essex
Field Club, July 22, 1882, and will be found iu the “ Proceedings ” of the
Club (Vol. iii.).
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