276 BOTANICAL GAZETTE [APRIL 
sylvestris, the male pronucleus is many times smaller than the 
female. In the present work, although the male pronucleus was 
often observed within the oosphere, no case was found in which 
the pronuclei were just coming into contact. 
One fine preparation was obtained which shows the chro- 
matin of the two pronuclei within the original limits of the 
female pronucleus (fig. 20). Both pronuclei are in the spirem 
stage, and show the chromatin granules evenly distributed upon 
a delicate linin thread. The kinoplasmic threads seem to be 
developing almost exclusively in the region of the male pron: 
cleus, but it is hardiy safe to draw any conclusions. A later 
stage, which I am not ready to interpret, is shown in jig. 2! 
The spirem thread has become perfectly smooth and has the 
same diameter as a chromosome in the anaphase of the first 
division of the fusion nucleus, but the segmentation into chro- 
Mosomes is not yet complete. It seems possible that the upper 
group represents the male pronucleus, and the lower the 
female. 
The first division after fertilization (fig. 22) shows beautifi! 
figure with a very strongly developed spindle, some of its kine 
plasmic threads reaching from pole to pole while others gee 
insensibly into the surrounding groundwork of the nucleus. ; 
; econ 
chromosomes are very definitely U-shaped. After the s e 
_ division has taken place and the four free nuclei have pane 
move toward the base of the oospore, they show a pea 
tangential striation (fig. 23) which seems to be caused by ae 
tion of the nuclei as they descend. In the first division 0 ‘n 
four nuclei, after they have reached the base of the meee is 
24, 242), the spindle is extremely broad and mule lar 
later divisions (figs. 26, 26a) the spindle is of the usual bip? 
type. This figure givesa typical view of the U- 
: oming 
Somes as they appear in these divisions, just before gee in 
Separated from each other. Although several ea") a aa 
mitosis were found in the nuclei of the partially eT tet 
tion of the oospore s. 25, 25a), no later stages WET pore 
pore (figs. 25, 25a), mitosis in § 
A fairly complete series was obtained showing 
