tn 
36 BOTANICAL GAZETTE [JULY 
rounded by an epidermal layer (fig. 1). The hypodermal arche- 
sporial cell usually gives rise to two sporogenous cells; and one 
case of three sporogenous cells was discovered. In every case when 
observation was possible, the outer sporogenous cell developed the 
embryo sac. At the same time, the epidermal cells at the tip of the 
nucellus divide periclinally. No evidence was found to indicate that 
" a primary parietal cell is ever cut off by the archesporium. 
_Empryo sac.—As the ovule develops, the funiculus increases 
greatly in length, and this is accompanied by a corresponding length- 
ening of the outer integument (fig. 2). At the same time the integu- 
ments thicken considerably, and leave a narrow space between the 
nucellus and the inner integument. The embryo sac lengthens 
downward and encroaches somewhat on the chalaza (fig. 3). Prepa- 
rations of sacs were obtained containing two, four, and eight nuclei. 
In the preparation represented in fig. 3 (three sections of a single 
sac) there were eight active nuclei, but also traces of several degenerate 
nuclei, apparently indicating that more than eight nuclei had been 
formed. In fig. 3a there appears to the left a small nucleus with 
feebly defined boundary, but abundant chromatin contents; two 
similar but smaller nuclear fragments appear in fig. 3b. All this 
perhaps indicates the presence of ten or twelve nuclei in the embryo 
sac, some of which break down. — 
Three of the eight active nuclei form the egg-apparatus (jig. 4). 
Fusion of the polar nuclei was not demonstrated, nor were any of the 
phases of fertilization well shown except in one case (jig. 12). 
The number of antipodals is variable; for example, there are 
three in jig. 5, two in fig. 6, and four in fig. 11. 
ENDOSPERM.—The endosperm begins with free nuclear division. 
Whether it originates from a single endosperm nucleus, or by direct 
divisions of six of the eight nuclei previously figured could not be 
satisfactorily determined. In fig. 5 walls are beginning to appear 
between the free nuclei and it seems that the wall-formation begins 
at the middle of the sac and proceeds toward the ends. 
The walls of the endosperm cells soon become heavy (figs. 6, 7, 8): 
When the embryo reaches the stage shown in fig. 8, the thickening 
of the endosperm walls is complete, and the nuclei begin to show a 
tendency to disintegrate, . 
