316 BOTANICAL GAZETTE | NOVEMBER 
center. The embryo sac increases in width in the four-celled 
stage (figs. 4, 5), and when it has reached the eight-celled 
stage it has a decided curvature (fig. 6). Many of the eight- 
celled embryo-sacs were destroyed or rendered worthless for 
camera drawings because they were cut and scattered through 
too many sections. The one figured has been sectioned so as 
to cut off the antipodals. It is probable that one is looking at 
them from above rather than in side view, as the rest of the 
figure appears. During the last divisions of the embryo sac the 
tapetal cell disappears ( figs. 5, 6). 
Up to this point the nuclei are uniform in size, but after the 
conjugation of the polar nuclei the definitive nucleus is easily 
distinguished by reason of its superior size, the presence of 
numerous refractive particles in its large nucleolus, and _ the 
readiness with which it stains. The presence of refractive 
bodies is not peculiar to the nucleolus of the definitive nucleus 
alone, but is found in less degree in the endosperm nuclei and 
in the large nucleus of the basal suspensor cell. It may also be 
true of other nuclei, but is not noticeable on account of the 
diminutive size. 
After the definitive nucleus is formed, the egg apparatus 
(figs. 7-9) is readily distinguished, but in the majority of cases 
the antipodals have entirely disappeared. They are either 
absorbed or destroyed by the progress of the embryo sac in its 
encroachment upon the lower part of the nucellus, crushing and 
crumpling them out of shape. In many cases the lower part of 
the nucellus is contorted and pushed aside by the advance of 
the embryo sac, indicating a remarkable degree of force exerted 
from within (fig. 72). Where remains of antipodals were found, 
that end of the embryo sac had evidently slipped between the 
nucellus and its integuments and had not been subjected to the 
usual ordeal ( figs. 35-36). 
The oosphere is well concealed by the synergids (igs. 8,9) 
until after fertilization, when its nucleus descends into the 
lower part and the oospore (fig. ro) begins to elongate rapidly 
(jigs. r1, 12). Upto this time the definitive nucleus remains 
