82 McKenney—Observations on the Development 
fundament. Following the formation of the secundine funda- 
ment the primary tapetal cell usually divides by a periclinal 
wall into two cells. By these successive divisions, the arche- 
sporium becomes pushed down into the tissue of the nucellus, 
so that, instead of lying just beneath the epidermis, it is 
separated from it by a chain of three cells (Plate XI, Fig. 3). 
The archesporium now passes through a growth period of 
considerable duration. After the growth phase, the arche- 
sporial nucleus divides and the archesporium becomes divided 
by a periclinal wall into two equal-sized daughter cells. 
(Fig. 4). I have only been able to observe this division in 
the anaphase and telophase stages. The anaphase stages 
observed, however, were quite clear and the number of chro- 
mosomes could be readily counted. The number of chromo- 
somes, which in this division enters into the formation of the 
daughter nuclei, is eight (Fig. 4a). All the divisions of the 
surrounding nucellar cells and the first division of the arche- 
sporium show sixteen chromosomes. Hence it seems quite 
probable that this last division of the archesporium is the 
reduction division. 
Of the five cells formed by the division of the primitive 
archesporium, the three outer remain inactive while the two 
inner grow actively until they become two to three times as 
large as the outer three. Attendant on this great growth of 
these daughter cells of the archesporium, is a gradual degen- 
eration of some of the neighboring nucellar cells. The outer 
of these two daughter archesporial cells is the young embryo- 
sac cell. The nucleus of each of these cells divides, but no 
cell wall is laid down between the daughter nuclei. Thus two 
bi-nucleate cells are produced (Fig. 5). The inner bi-nucleate 
cell becomes passive for a time. The outer bi-nucleate 
(embryo-sac) cell, however, elongates until it becomes about 
twice its former length. The bi-nucleate cells again become 
active and by the division of each nucleus two quadri-nucleate 
cells are produced, the nuclei of the outer bi-nucleate cell 
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