374 
opinion he was followed by many 
others, 
In 1774, however, a physician at 
Chemnitz, John Hedwig, since so justly 
celebrated, observing in the stellate leaves 
of several mosses some cylindrical cor- 
puscles, which had been discovered a 
long time before by Micheli, perceived 
that they were open at the end, and 
emitted a powder of. great tenuity; he 
hence concluded that they were the an- 
thers. 
Having afterwards sown the dust con- 
Jained in the capsules, he saw moss spring 
up, from which he inferred that this 
dust was theseed, as had been frequently 
conjectured before his time, and that 
consequently the capsule was the fruit, 
or fecundated female organ. 
These observations were first publish- 
ed in an abridged form, during 1777; 
they received the approbation of the 
academy of Petersburgh in 1781, and 
for more than thirty years have been in- 
vestigated with the most persevering at- 
‘tention, and elucidated by copious works 
and various designs executed by the aid 
of the microscope. At present, they 
have obtained the approbatiun of the 
generality of European botanists, espe- 
cially of those who have made the mosses 
a particular object of study. The only 
plausible ohjection, and one that was at 
first warmly urged against this doctrine, 
namely, that certain genera of mosses 
are destitute of steliate leaves, has been 
nearly overturned by Hedwig, who, with 
the most indefatgable industry, succeed- 
ed in demonstrating, that, in these cases, 
the anthers are contained in the buds of 
the axille of the leaves, or rather that 
they accompany the base of the pedicel 
of the capsule; im short, he has shown, 
that they are present in nearly all the 
genera. 
This system, appareutly so well sup- 
ported, is notwithstanding contested 'by 
M.de Beauvois. Wis intention is to sub- 
stitute, in its stead, one which he pre- 
sented to the Academy of Sciences of 
Paris, in 1782, and which is founded on 
the following data :— 
In the midst of the dust, contained in 
the capsule, which Hedwig regarded as 
the seed, is a kind of nucleus or small 
axis more or less swelled, termed by the 
botanists a columelia. Vhose, by whom 
it was noticed, conceived it to be paren- 
chyma of a more or less cellular texture, 
Hedwig himself ‘represented it several 
tines under this form; but M. de Beau- 
~-¥ois inferms us that he has noticed some 
=> 
Proceedings of Learned Societizs. 
[Nov. f4 
verysmall bodies attached to it, which 
he supposes to be the true seeds, and the 
dust by. which they are surreunded, is, in 
his opinion, the pollen. The motion of 
the cilia, when they are present, he con- 
ceives, is intended tocompress the pollen 
against the seeds, in order to facilitate 
their fecundation at the instant they are 
about to escape. According to M. de 
Beauvois, the capsule is hermaphrodite, 
and the complex apparatus of the organs 
taken by Hedwig for anthers, and which 
is found in most of the mosses, is of ne 
use, so far as we have hitherto been able 
to discover; the individuals of certain 
species, which bear star-like leaves only, 
are sterile; the pollen is larger and more 
abundant than the seed, the latter of 
which is only visible after the most ac-. 
curate examination; and is not fecun- 
dated in the ovary, as in other plants, 
while yet tender and small, but at the 
moment of its escape, and after it hag 
been completely evolved; in short, if it 
be asked. how M. Hedwig produced 
mosses by sowing what M. de Beauvois 
reckons the pollen, the latter will answer, 
that, in conjunction with it, Hedwig 
-also sowed, though unknown to himseif, 
the real, but almost invisible grain. Ie 
may be thought that in order to confirm 
so singular an opinion, this grain should 
not only have been exhibited, but sown. 
separately, and detached from the sup- 
posed pollen; unfortunately, however, 
this last e..periment has not been made, 
and we may judge from the above detail, 
that it is next to impossible to put it,in 
execution. 
M. de Beauvois maintains similar opi- 
nions with respect to the fructification of 
mushrooms. seh) 
Different parts of these plants, such as- 
the gills or lamella of the agaric (agaricus», 
the points of the hadnum, Ac. are cover- 
ed at a certain period with a profusion of 
small grains, or dust; other genera, such 
as the trutfle (dycoperdon), have their in- 
ternal parts filled with a similar sub- 
stance, which they discharge on arriving 
at maturity. All those betanists who 
contend that mushrooms are furnished 
with seed, conceive these grains to be 
the seeds, or capsules. M. de Beauvois, 
on the contrary, is of opmion, that it i$ 
the pollen, and affirms, that the seeds are 
contained within the gillsand points or in 
some other part of the plant, and that — 
they have hitherto escaped observation, 
from their extreme minuteness. It is at 
the moment of explosion, and conse- 
quently after they are fully evolved, 5 
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