130 BOTANICAL GAZETTE [AUGUST 
to which it may be suggested that there is an elongation of the 
nucellus during the growth of the gametophytes, together with a 
digestion of that portion of the nucellus immediately adjacent to 
them. The megaspores were evidently in contact when formed, 
but by the enlargement of the pollen tube between the young 
gametophytes they become widely separated as the tube develops. 
Fertilization 
While the fertilized egg represents a new phase in the life 
history and the account of it might be more properly included 
with that of the embryogeny, it may not be out of place to give a 
brief account of it in this connection. Ovules containing pro- 
embryos were found in material collected May 21. Preparations 
showing fertilization were found from this time on to as late as 
the middle of June, showing that the time for fertilization is not 
constant and may have considerable range. 
At the time of fertilization the neck of the archegonium becomes 
ruptured and the nuclear contents and part of the cytoplasmic 
contents of the tube are discharged into the egg. The egg nucleus 
has migrated to the basal portion of the egg; the male nucleus with 
its investing cytoplasm comes in contact with the egg nucleus; the 
_ cytoplasm of the male nucleus invests the two nuclei lying in con- 
tact and forms a dense sheath about them (fig. 56). With the 
_ fusion of the two nuclei the act of fertilization is complete. The 
behavior of the chromatin in fertilization could not be determined 
from i —— The cytoplasmic sheath about the two nuclei 
also in Torreya californica (11), T. taxifolia (14), and Cephalo- 
taxus : Fosteass (16) among the Taxaceae, as well as in several other 
cases reported, namely, by CoKEr (8) in Taxodium; by Lanp (13) 
i Ephedra; and poe NICHOLS (x9) in Juniperus communis var. 
| -— 
"The smaller male cell and the stalk and tube nuclei, together 
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a a 
, when hen present, , 
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ryoorevenafter 
ae — —— _ may persist st for some time and _ 
- 2cog mz — t some Seige s of the p : 
