Of the two forms of fructification, it has been most clearly
proved by Kaulfuss and Vaucher that the nucules are reproductive,
and more recently by Mr. Varley ; and it is
not difficult to understand how their outer wall is formed
by the union of the several divisions of a whorl, and the
germ within by the central bud, which would otherwise
have been evolved. The nucules, then, may be either
gemmae, or real capsules. As regards the globules, Wall-
roth asserts that he has raised young plants from them,
and considers them as analogous to what Hedwig calls
anthers in mosses and to the gemmae of certain perfect
plants. His observations do not appear to have been
verified by later writers. Meanwhile it is desirable to
have a correct notion of their structure, by which means
alone they can be viewed in the relation of their several
parts to those Organs of the plant of which they are doubtless
modifications.
Before I proceed to give my own description, it may be
well to state what has been said by the latest writers whose
observations I have met with. In the beginning of his paper,
(published in 1826 in the Nov. Act. Phys. 8fC. vol. 13,
pt. 1. p. 123,) Uber die Anatomie und den Kreislauf der Cka-
ren, Agardh gives no certain account of the structure of
the shell of the globules. He figures the cup-shaped bodies
to which the conferva-like filaments within the globule
more by the course of the water, but is occasionally affected by the tide :
that at Cley was very near the beach, and the water in it probably brackish
; but of this I am not accurately informed. The plant from which
the principal figure in Engl. Bot. was drawn, was from a ditch at Lancing,
which I believe the tide never reaches,—not, as erroneously stated, from
Shoreham Harbour. In this the thread was more slender, and, I think,
of less entangled growth; the globules stood singly on a longer pedicel,
and no nucules were produced. I believe the distribution of the bracteas
was as described above, although it is not well represented in Sowerby’s
figure.
“ Perhaps the following character may serve to distinguish this species:—
“ Chara nidifica, filo lsevi, ramulis articulatis indivisis apiculatis, brac-
teis quaternis semiverticillatis divaricatis filiformibus nucula pluries longi-
oribus.
“ Of the other British Nitella, already observed, I do not yet understand
C. translucens, although I believe it distinct; and C.flexilis and C. gracilis
are distinguished from C. nidifica and from each other thus :—
“ C. fiexilis has its ramuli di-trichotomous;
“ C. gracilis, doubly trichotomous.
“ How far these characters may be common to other species I know n o t;
nor whether Agardh’s species of the same names are synonymous with
the plants of Engl, Bot., which are what I have in view.”—W.B.
are attached, but he could not discover how these cups
were disposed. “ They seem,” he says, “ to give rise to
the rays of the star-like spots upon the surface of the globule,
so that they lie towards the surface, while the threads
are towards the centre. They are not however equal in
number in every globule ; they are easily separable from
the threads attached to them, and soon lose the red pigment
with which they are filled.” ,
This account agrees only in part with what I have observed,
and with the figures very recently given by Mr.
Wilson. When the paper was already dispatched, Agardh
met with Kaulfuss’s Erfahrungen über das Keimen der
Charen. Kaulfuss’s account of the red globules differed
from Agardh’s, in that, at the closed end of the cup, where
Agardh saw the filaments fastened, he perceived little bulbous
bladders. These might be the scars of the filaments.
Kaulfuss determined also that the cups are fastened to six
of the superficial stars in the centre of the radii.
With regard to the number of divisions into which the
globules split, Agardh could make no accurate determination.
Kaulfuss specifies three, Wallroth 3—4, in which
Dr. Hooker and Dr. Greville seem to coincide with
him. Dr. Ackermann and Mr. Wilson alone seem to have
discovered the real number, exactly eight, each being a
precise eighth of the spherule.
I should have thought it needless to publish the present
observations, had Mr. Wilson’s been made on the fructification
of a species of Nitella, in which, from the larger
size and less incrusted coat, it is much easier to observe
completely ; as he doubtless would have left nothing worthy
of recording. The little additional matter I have to offer
(the question of the disposition of the cups being already
determined by him,) relates to the disposition of the rays,—
and a conjecture as to the probable mode of origination of
the globules. The latter point however cannot be satisfactorily
determined without an examination of the contents
of the globules in different stages of growth ; and this
could scarcely be done with any hope of success except in
the largest species of Nitella, which I have never yet had
an opportunity of examining. When a complete notion
ol’the structure and theory of the globules shall have been
thus obtained, we may hope at last to discover, with some