430 Lawson . — The Gametopkytes , Fertilization and 
again at right angles to the first division. The mature archegonium has 
therefore at least four cells in the neck. These are shown very well in Fig. 
38, as they appear in cross-sections. In but a single case was I able to find 
a variation from this number, and that was in a longitudinal section where 
four were observed, suggesting that there may have been eight altogether. 
It appears that in the Conifers the number of neck-cells is not always 
constant. According to Coker (’01), they may vary from two to twenty- 
five in Podocarpus. In Sequoia (Lawson, *04) they may be two to four. 
In Taxodium (Coker, ’03) they vary from two to sixteen or more, and 
they also vary in Tsuga (Murrill, ’00). In Cryptomeria the neck consists 
typically of a single tier of four cells (Fig. 38). 
By the time the neck-cells have been organized the central nucleus 
enlarges considerably, and shows all the characteristics of a nucleus preparing 
for division. Fig. 41 shows a section of the nucleus in this condition. 
The large nucleolus has disappeared and the chromatin has assumed the 
form of definite chromosomes. The spindle showing the actual division of 
the central nucleus, and which gives rise to the egg and ventral canal- 
nucleus, was not found ; but from the observations made it seems tolerably 
certain that such a division takes place. Many archegonia at this stage 
showed two distinct nuclei, and one of these is shown in Fig. 36. The 
results of investigations during the last few years make it appear that 
the cutting off of the ventral canal-cell or nucleus is very general, if 
not universal, among the Conifers. Such a cell or nucleus has been 
found in Juniperus (Strasburger, 79, Belajeff, ’93) ; Pinus (Blackman, ’98, 
Chamberlain, ’99, Ferguson, ’01) ; Taxodium (Coker, ’03) ; Podocarpus 
(Coker, ’02) ; Tsuga (Murrill, ’00) ; Thuja (Land, ’02) ; Sequoia (Lawson, ’04) ; 
and Picea (Miyake, ’03). In many of these forms all the stages of mitosis 
have been carefully followed, so that there can be little doubt that such 
a division of the central nucleus occurs in these Conifers. Owing to the 
fact that Arnoldi denies the existence of a ventral canal-cell or nucleus in 
Cryptomeria , I have been very careful in my observations. Although I was 
unable to find the spindle, there was nevertheless enough evidence to 
convince me that such a division takes place. In a large number of 
archegonia, just before fertilization, two distinct nuclei were observed in the 
cytoplasm. That this second nucleus was not the male nucleus in the act 
of fertilizing the egg was very obvious, from the fact that the neck-cells were 
in no way disturbed, and in nearly every case the male cells were to be 
seen in the pollen-tube above the archegonia. When we consider that the 
stage immediately preceding this showed the central nucleus preparing for 
division, I have little hesitation in considering the second nucleus in the 
archegonium to be the ventral canal-nucleus. In Fig. 36, the ventral canal- 
nucleus is already showing signs of disorganization. It presumably lasted 
but a short time, for it was not found in the stages during or after fertiliza- 
