106
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branches horizontal, bearing two or three series of alternate capillary
pinuæ and pinnulæ, exhibiting no appearance of articulations, the uppermost
ones having their apices rolled in. Fructification : 1. minute
axillary roundish capsules, according to Roth. 2. lanceolate, pod-like
receptacles terminating the ramuli, and containing ternate granules.
Substance cartilaginous, tender. Colour pale purplish, pellucid.
In drying it becomes blackish, and does not adhere to paper.
The structure of this alga is so curious that there can hardly be a
doubt of its removal, at some future period, from the genus. A transverse
section of the stem, shews nothing but a tissue of hexagonal
cells, each marked with a red central spot. A longitudinal section shews
the cells, forming parallel longitudinal series, each cell being about twice
as long as it is broad : through each line of cells runs a filament, dilated,
oblong-elliptical, and of a red colour within the cells, contracted
and colourless as it passes through the ends of the cells. In cutting
transverse slices of the stem, upon the table of the microscope, portions
of these filaments escape. Mr Turner probably saw them, when
he observed the frond to be streaked with faint, longitudinal parallel
lines, and I agree with him in his remark, that it possesses some affinity
with Conferva polymorpha [Polysphonia fastigiata). It may indeed
be said to form one of the intennediate links between all the Polysi-
phonicB and the continuous Algce : there is not, however, any articulation
even in the young ramuli. Until the capsules shall be examined,
and their nature ascertained, it may remain with little inconvenience
in this place.
G e n u s X X X I. BONNEMAISONIA, Ag. Tab. X III.
Ge n . C h a k . Frond membranaceous, compressed or, plane,
filiform, much branched, the branches pectinate with
distichous ciliæ. Fructification, sessile or pedicillate
capsules, containing a cluster of pyriform (compound ?)
seeds fixed hy their base.
O b s . Too little is known of the fructification of this genus (named
.after a celebrated French Algologist, of the name of Bonnemaison), to
allow of its being considered as perfectly well defined. There ai'e only
three species described, and, it must be confessed, that in regard to habit
they assimilate, and are strikingly different from other Algoe. I have
only seen the capsules of the British B. asparagoides, and they greatly
resemble those of the genus Laurencia ; but the seeds are compound,
that is, contain within a pellucid border a number of granules, in the
same manner as those of Cutleria multifida. It is not improbable that
a second modification of the fructification remains to be discovered ;
and that, although the habit of the genus is quite peculiar, it will still
farther contribute to distinguish it. Agardh’s character, “ Semina
pyriformia concatenata,” I do not understand, unless he so defines the
appearance of the granules of which the seeds are composed.
I. B o n n e m a i s o n ia a s p a r a g o id e s . Tab. X III.
Frond compressed conferva-like very much branched capsules stalked
alternate and opposite to the ciliæ.
Bonnemaisonia asparagoides, A g . S p . A lg . v . 1. p . 197- S y s t. A lg . p . 246. S p r e n g . S p .
P I . V. 4. p . 333.
Plocamium asparagoides, L am o u r . E s s a i, p . 50.
Fucus asparagoides, W o o dw , in L in n . T r a n s , v . 2. p . 29. t . 6 . Sm . E n g . B o t . t . 571.
T u r n . S y n . F u c . p . 364. H i s t . F u c . t . 101.
H a b . On rocks and stones in the sea, very rare. Annual. June
to September. Yarmouth Beach, Mr Wigg. At Cromer and Sheringham,
Turner. Coast of Cornwall, Stackhouse. Sunderland Beach,
Mr Weigh ell. At Gorton and Gunton, Suffolk, Mrs Fowler. Bantry
Bay, Miss Hutchins. Donaghadee, Mr Templeton. Bangor, near
Belfast, Dr Drummond.
Root a minute disk. Frond six to nine inches long, and hardly half
a line wide in the main stem, compressed, attenuated, distichously
branched : branches several inches long towards the base, set with
two or three lesser series, and all of them bearing distichous ciliæ or
subulate ramuli about a line in length, resembling the teeth of a comb.
Fructification ; stalked ovate minute capsules, with a terminal pore,
alternating with the ciliæ, in such a manner that a capsule is placed
opposite to a cilia first on one side and then on the other ; within is a
cluster of pear-shaped stalked seeds fixed by their base.
Substance soft, flaccid, and membranaceous, adhering to paper in
drying. Colour a pale transparent crimson.
An extremely elegant and beautiful plant, resembling a finely
branched Conferva when growing. The subulate ramuli seem to be
really alternate, as Roth has described them, and not opposite, as
Mr Turner is inclined to believe. The capsules ai'e uniformly oppo