Scientific Reviews. 197 
in the same manner as the reproductive corpuscles of some con- 
ferve are capable of spontaneous movements, before they become 
fixed, to form as they grow up, a new plant. He considers that it 
is a character common to the reproductive corpuscles of all organ- 
ized beings, to enjoy a peculiar existence which manifests itself in 
spontaneous motions. * 
The theories of Mr. Brongniart are founded, in the first place, 
upon the analogies of the spermatic granules of ‘vegetables, with the 
spermatic animalcules of animals, analogies which are doubtful and 
imperfect ; and, in the second place, upon the nature and the func- 
tions which, according to a certain system, have been attributed to 
spermatic baimaleule - but this system, according to the reporters, 
is far from being beyond the reach of contestation, and the intro- 
duction and transmission of the granules through the vegetable 
tissue, as far as the germs of the ovulum, present new difficulties in 
the theory of vegetation. 
In addition to the observers already mentioned, Mr. Guillemen, in 
his Recherches Microscopiques sur le Pollen, read before the 
Academy in 1825, had stated that when the grains of pollen are 
burst in water, that a kind of stream is produced by the ejection of 
a denser liquid in which the granules move at first with great ra- 
pidity ; but that motion ceases very soon. He thought that these 
granules have a life independent of the organ which encloses them, 
aaa that they are the rudiments of embryos which nature carries 
upon other parts necessary for their developement. 
Mr. Brown’s researches, entitled a Brief Account of Microsco- 
pical Observations made in the Months of June, July, and August, 
1827, on the Particles contained in the Pollen of Plants ; and on the 
General Existence of Active Molecules in Organic and Inorganic 
Bodies, was not put into circulation by the author till the month of 
July or August 1828, and was printed without the author’s sanction 
in Professor Jameson’s Journal for September in that year. These 
observations were not then publickly known until that period, before 
which, on the 10th March 1828, Mr. Raspail read to the Academy 
an essay, entitled Experiences et Observations destinées a demontrer 
que les granules lancés dans U explosion du Pollen, bien loin d'etre 
les analogues des animalcules spermatiques, comme Vavort avancé 
Gleichen, ne sont pas meme des corps organisés. The labour was 
divided into two parts. In the first part the author examined the 
accidental causes, which, without the observer’s knowledge, may 
impress upon the stillest corpuscles the most deceitful motions. 
These causes he supposes to be, Ist The explosion which ejects the 
sranules. 2d. The phenomena of capillarity. 3d. The evapora- 
tion of the water on which the granules are floating. 4th. The 
evaporation of the volatile substances with which the floating gran- 
ules may be impregnated. 5th. The motions common to great cities. 
6th. The motions impressed by the agitation of the air. 7th. The 
motion occasioned by the pressure of the observer’s hands upon the 
table. 8th and lastly. The inclination of the supporting glass. 
