196 Scientific Reviews. 
tissue of certain spongy stigme, and to all appearances allows the 
fecundating granules which it contains to be poured out in that si- 
tuation. ‘This was the state of the question in its first days, and the 
subjects of discussion were the probability of certain stigme being de- 
prived of epidermis, while the utricule were in other plants covered 
with that membrane,—the degree of adhesion which existed between 
these utricule, and the real importance of the intervening mucilagin- 
ous matter, to which may be added, the degree of credit which 
could be attached to Mr. Brongniart’s statement of his having seen 
the grain of pollen introduce its membranous cylinder between the 
interstices of the utricule, and, bursting there, spread its granules 
among the inter-utricular cavities of the stigma down to the style, 
and which he had seen travel from thence to the ovulum itself. 
And it was asked with great plausibility, how was it possible to 
see globules, almost incommensurable, travelling through a tissue, 
which offers in itself so many of similar dimensions, and generally 
so opaque that it is difficult to distinguish its internal tissue? And 
how, after dividing the ovulum longitudinally, could one be certain 
that the globules presented to the eye are the same as those seen 
in the grain of pollen ? 
Tn his first essay read before the Academy of Sciences, Mr. Ad. 
Brongniart had assimilated these incommensurable granules to the 
spermatic animalcule of animals; but as the reporter passed over 
this part of the subject in silence, he presented to the Academy, 
on the 5th November 1827, a supplementary labour, in which he 
definitely stated his agreement with Needham, Gleichen, Geoffroy, 
Spallanzani, and others, in considering the granules of the pollen 
as analogous to the spermatic animalcule of animals, and in contra- 
diction to the opinion of Kcelreuter, and the generality of his suc- 
cessors, who attribute fecundation to a very subtle and invisible 
uid. Mr. Cassini, in the name of himself and Messrs. Mirbel and 
Desfontaines, reported on this essay, in which they considered cer- 
tain general laws as very premature. Mr. Brongniart had assert- 
ed, for example, that the species of the same genus presented gra- 
nules of an analogous form, and that differ a good deal in different 
genera, even in the same natural families ; and he thought that he 
could explain, by these facts, how the production of hybrids is easi-- 
ly effected between plants of the same genus, and why it is impos- 
sible under other circumstances. 
Not only did Mr. Brongniart see the granules of many plants 
change their position with respect to one another, by approximating 
and distancing ; but what is more remarkable, he saw the oblong 
granules of the Hibisci and @inothere curb themselves spontane- 
ously in the form of an are, or even the form of an S, but always 
very slowly. Considering that the cause of the metion can only 
reside in the granules themselves, Mr. Brongniart thought that it 
could be qualified as spontaneous, and as the molecules of all organic 
Huids are motionless from the moment that they leave the body of 
the animal, with the exception of those which constitute the sperm ; 
