Fecundation in Orchidee and Asclepiadee. 109 
opake speck is the commencement of the future embryo. At 
this period, or until the opake corpuscle or nucleus has acquired 
more than half the size it attains in the ripe seed, a thread may 
be traced from its apex very nearly to the open end of the testa, 
or as it may be supposed, to the apex of the original nucleus of 
the unimpregnated ovulum. 
This thread consists of a simple series of short cells, in one of 
which, in a single instance only however, I observed a circu- 
lation of very minute granular matter; and in several cases 
I have been able to distinguish in these cells that granular 
areola so frequently existing in the cells of Orchideous plants, 
and.to which I shall have occasion hereafter to advert. 
The lowermost joint or cell of this thread is probably the 
original state of what afterwards, from enlargement and depo- 
sition of granular matter, becomes the opake speck or rudiment 
of the future embryo. 
The only appreciable changes taking place in this enki 
rudiment of the embryo are its gradual increase in size, and at 
length its manifest cellular structure. 
In the ripe state it forms an ovate or nearly spherical body, 
consisting, as far as I have been able to ascertain, of a uniform 
cellular tissue covered by a very thin membrane, the base of 
which does not exhibit any indication of original attachment at 
that point; while at the apex the remains of the lower shrivelled 
joints of the cellular thread are still frequently visible. 
This cellular body may be supposed to constitute the Embryo, 
which would therefore be without albumen, and whose germi- 
nating point, judging from analogy, would be its apex, or that 
extremity where the cellular thread is found ; and consequently 
that corresponding with the apex of the nucleus in the unim- 
pregnated ovulum. 
The description here given of the undivided embryo in Orchi- 
deous 
