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,190 S I PHONEAi . [ Vaucheria.
the young plant has heen frequently traced hy means of the micro-
scope.
One of the species of Vaucheria ( V. clavata) is connected with an
extraordinary theory, recently prevalent in Germany, that some vegetable
bodies possess successively an animal and a vegetable nature, and
that tliey pass from one state to the other without disorganization. This
theory is considered to apply to the Oscillatorice, a tribe of Algce, which
exhibit a kind of motion ; to tbe Protococcus nivalis or colouring matter
of tbe Red b'now, and some other minute plants. Tbe observations
upon the Vaucheria clavata were made by M. Franz Uno-er
He watched the filaments till they developed their terminal vesicles •
lie saw the summit burst and the vesicle escape; but, instead of becoming
at once quiescent as a vegetable organ might be expected to
become, ,t swam about, in all respects like an animal endowed with
voluntary locomotion. After having been exceedingly active for about
the space of an hour, the globule slightly changed its form and colour,
lost Its apparent animality, became stationary, and in a short time put
forth, first, a radicle, then a stem, fixed itself to the nearest substance,
and m about eleven days bore fructification in its turn. These singular
observatmns were many times repeated by M. Unger, with the same
result. The subject is a curious one, and in whatever way the appearances
are to be accounted for, they are exceedingly interesting, and
snoula be farther investigated
* Vzsicles solitary.
1. V a u c h e r ia d ic h o t o m a .
hrond setaceous dichotomous fastigiate, the vesicles solitary globose
sessile. • ®
U 'r U T i - X V i : -■ ■■ "■-■
la u c lM ia diohotoma, v a r . submaruu., L y n g b . H y d r o p h . D a n . p 76, t . 20.
Hab In ponds and ditches. Annual. Spring and summer. Common
Var. g. At Weymouth, Rev. M. J. Berkeley.
Plant growing at the bottom of ditches, and often tilling them with
• s entangled matted nearly erect fronds, which are as thick as a hog’s
fon;:rr:;r ~ i n „ t e n e s s i „ t b e
Vaucheria.] S I PHONE 7 E . 191
bristle, a foot long or more, dicbotomously branched towards the upper
part. Fructification solitary, subglobose, sessile, dark green vesicles,
scattered upon the branches, and visible to the naked eye. Substance
membranaceous. Colour generally a pale transparent green, but
sometimes dark and even blackish. In drying, it does not adhere to
pajier.
The largest of the genus, being sometimes two feet in length. Sir
James F. Smith, from its size and appearance, conjectured it might even
belong to Chara, and thought he saw some resemblance between the
vesicles and the capsules of that genus. This, however, it is hardly
necessary to observe, was quite an erroneous view: the species agrees
in all its generic relations with the rest. After maturity, it separates
from its attachment, and floats in faded and large masses on the surface.
The variety submarina is much finer in the frond, only a few inches
long, and the vesicles mostly ovate-elliptical. My friend Mr Berkeley
did me the favour to communicate a specimen from Weymouth.
2. V a u c h e r ia D i l l w y n i i . Tab. XIX.
Fronds flexuose, forming a thin terrestrial stratum, the vesicles lateral
sessile globose,
Vaucheria Dillwynii, Ag. L y n g b . H y d r o p h . D a n . p . 77* t . 21. Ag. S p . A lg . v. 1 . 1). 464.
S y s t. A lg . p . 173. G r e v . F l . E d in . p . 305.
Ceramium Dillwynii, R o th . C a t. B o t. v . 3. p . 117-
Conferva frig id a , D illw . B r i t . C o n f . t . 16.
H a b . On the ground in damp shady places, ditcli-banks, &c. Annual.
Spring and autumn. Very common.
Fronds scarcely more than an inch long, flexuose, irregularly branched,
nearly of equal thickness throughout, obtuse at the extremity, forming
a thin interwoven stratum. Fructification, scattered globose sessile
vesicles, darker than the frond. Substance membranaceous. Colour
a bright green.
A very common species on the bare soil under shady hedges and
similar situations, forming a continuous stratum of a deliglitfnlly soft
green colour.
3. V a u c h e r ia t e r r e s t r is .
Fronds straight, forming a lax somewhat bristly terrestrial stratum, the
vesicles lateral hemispherical on the side of a horn-shaped peduncle or
rather receptacle.
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