ON THE EMBRYO OF TROPQOLUM MAJUS. 625 
observer, on account of the extreme tenuity of the mem- 
brane, but I am quite satisfied that it exists. 
In Giraud’s “fourth period” after impregnation, the 
primary utricle, at its lower extremity, next to the base of the 
nucleus, is said to be terminated by a spherical mass of cells, 
constituting the first trace of the embryo ;” and its upper por- 
tion * at this period assumes the character of the suspensor,” 
(Mirbel) which subsequently protrudes its upper extremity 
* through the apex of the embryo-sac, the apex of the 
nucleus, and the micropyle;” and from this extremity a 
number of cells * hang loosely in the passage leading to the 
conducting tissue of the style." 
The Embryo makes its first appearance at the top, and not 
at the bottom of the cavity of the nucleus ;—when it has 
reached the lower part of the ovule it is in a state consi- 
derably advanced, and is no longer spherical. 
In describing the Embryo, and its process, according to 
Schleiden, the primary article consists of an oblong cellular 
body (the extremity of a pollen tube), with a lateral branch 
which bears the rudimentary embryo at its extremity. The 
whole is at first enclosed within the ovule, but subsequently 
* the coats of the ovule which cover it are obliterated ;" and 
while the lateral branch of this cellular body develops in the 
cavity of the ovule to form the embryo, the residue grows 
outside, and expands into a cellular cireumambient thread. 
The truth is, that this cellular body neither protrudes from 
the mieropyle; nor does it gain an outlet in consequence of 
the obliteration or * resorption" of the coats of the ovule :— 
on the contrary, it perforates the coats of the ovule immedi- 
ately below the micropyle, on the side most remote from the 
axis of the flower ; and instead of *loosely hanging cells in 
the passage leading to the conducting tissue of the style," I 
find a second process on the side next the axis of the carpella, 
which passes below the micropyle, into the cellular tissue 
which constitutes the neck of the ovule (containing amylon), 
and then proceeds down a minute channel in the substance of 
the carpellary integument parallel with the axis, ultimately 
