IN FLOWERING PLANTS. 169 
to be articulated on these. The pollen is singular: under an 
ordinary lens it appears reticulate, the spaces between the 
meshes being punctatedly opaque. This appearance under 
a triplet is cellular, with opaque, irregular, angular, areole ; 
but on changing the focus these opaque parts become lucid 
and yellowish, precisely the same as the pores of tissue are. 
The early development of the ovule I have not follow- 
ed; when nearly fully formed and totally inverted, it certainly 
has two integuments, of which the inner is slightly projecting. 
This subsequently. disappears, the neck and projecting part 
existing longest. 
e first change is the formation of the nucleary cavity; at’ 
the time of expansion, boyaux may be found passing into the 
foramen. I think they pass directly from the base of the 
style; no conducting tissue observed. 
The boyaux are occasionally branched, one is produced 
from one globule: in one instance several boyaux were anas- 
tomosed and interlaced in a curious manner, (requires fur- 
ther examination); the tube passes into the nucleus but a 
short way, in that represented; the apex of the inner coat 
remains. 
The next change is the production of the embryonary sac, 
which is developed from above downwards, and is of exces- 
sive tenuity, but perfectly membranous; it is soon filled with 
grumous molecules, especially at the apex or rather base, 
where the embryo is developed. This embryo is curious, its 
attachment is long, conical at top, dwindling below into a 
stalk, this is terminated by the globular embryo. See fig. 22 
for its cellular and granular composition. 
Lastly, the albumen developes and occupies the aloe of 
the embryonary sac ; the nucleus has been long reduced to a 
thin membrane. 
In the ripe seed the following parts will be seen: testa cori- 
aceous brown, nucleary membrane lining this and of great 
tenuity, embryonary sac distinct at the apex, albumen, and 
embryo. 
The embryonary sac will be at once known from the nu- 
cleary membrane if it present marks of its former attach- 
* Z 
