2 BOTANICAL GAZETTE [JULY 
The primary archesporial cell cuts off a tapetal.cell above, 
and then immediately forms the definitive macrospore below. 
The tapetum divides to three or four tiers of cells, which finally 
form, together with the outer layer of cells of the nucellus, a 
- persistent plug of yellowish thick-walled cells, directly under 
the micropyle (é#, figs. z, 2, 9, 73). 
The first four nuclei formed from the large macrospore 
nucleus are located at the periphery of the pretty dense proto- 
plast of the embryo-sac, arranged like the spores of a tetrad 
and connected by strands of granular cytoplasm (es, fig. 2). 
Soon after this we find eight ellipsoidal peripheral nuclei, 
imbedded in the cytoplasm surrounding the enlarged vacuole of 
the embryo-sac. Up to this stage the sequence of phenomena 
has not been very different from that in the normal angiosperm 
embryo-sac, except for the lack of the bipolar grouping usually 
found. But now each of the eight nuclei divides again, as 
Campbell has shown, to form an embryo-sac with sixteen similar 
nuclei, pretty uniformly distributed in the peripheral layer of 
cytoplasm (jig. 7). A little later than this, before the pollen 
tube reaches the embryo-sac, the cytoplasm begins to get denser 
about one of the nuclei at the top of the embryo-sac, and finally 
a definite limiting membrane surrounds this and forms the 
oosphere (0, fig. 1). This egg is not directly under the micro 
pyle, but is pushed aside slightly by the aggregation of a smaller 
amount of cytoplasm about a second nucleus at the top of the 
embryo-sac to form the single synergid, as we may call it from 
its position (sy, fig.z). The position of spindles in certain cases” 
seems to indicate that this is a sister cell to the oosphere. Some 
times other-nuclei are found near the egg, but often not, and in 
no case was there seen a definite massing of cytoplasm about 
any of these. At first the synergid does not have a definite 
wall, but later on, as it persists, at and after fertilization, a dis- 
tinct wall can be seen (sy, figs. 3, 7, 9, r7, f2), 
At about the time the pollen tube enters the egg certain of 
the remaining fourteen peripheral nuclei begin to move together 
to form a compact group, of usually eight nuclei, surrounded by 
