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1903] GAMETOPHYTES AND EMBRYO OF TAXODIUM LLy 
later stages the egg nucleus is nearly always furnished with 
but a single tuft on the side toward the base of the arche- 
gonium. The spindle may be situated in every position in 
reference to the axis of the archegonium, parallel (fig. 87), per- 
pendicular (fg. 88), or inclined (figs. 86, 89), but the inner 
pole is always located in the center of the aster. The spindle 
may extend either up or down from the inner pole, and the 
ventral canal nucleus may thus be placed either above or below 
the egg nucleus ( fig. 97). The archegonium to the right in 
jig. 92 shows a ventral canal nucleus situated nearer the base 
than the tip, and in the archegonium to the left the ventral canal 
nucleus occupies a nearly central position, the egg nucleus lying 
even lower. It is only rarely that the ventral canal nucleus is 
situated at the very tip of the egg. Such a position is shown in 
jigs. 87 and go. 
This formation of the ventral canal nucleus in any region 
other than near the tip of the archegonium has not been 
described in any other gymnosperm so far as I am aware. This 
peculiarity in Taxodium seems to be an acquired character for 
the protection of the ventral canal nucleus during fertilization, 
for, as we are to see later, it is to play a part in the subsequent 
history of the egg. In most gymnosperms the ventral canal 
nucleus is furnished with a certain amount of protoplasm of its 
own which is distinctly separate from that of the egg. Arnoldi 
(’00) lays stress on what he calls the absence of a ventral canal 
cellinCephalotaxus. He considers the ventral canal cell lacking 
because no wall is formed between the ventral canal nucleus and 
the egg. In this case, however, a certain amount of protoplasm 
becomes disorganized around the ventral canal nucleus, and 
swelling up is said to burst open the neck of the archegonium. 
If this is the case, the disorganizing protoplasm may be con- 
sidered as belonging to the ventral canal nucleus, and a ventral 
canal cell could not strictly be said to be absent. 
In Taxodium, however, not even a cell plate is formed, and 
the ventral canal nucleus lies perfectly free in the cytoplasm of 
the egg without a distinct protoplasmic area of its own. A 
ventral canal cell in the strict sense is therefore lacking here. 
