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1903} GAMETOPHYTES AND EMBRYO OF TAXODIUM 119 
nearer the center of the egg at about the time that those of the 
fertilized archegonia are dividing amitotically. In these cases it 
does not divide, but increasing greatly in size comes to resemble 
the egg nucleus just as in the case described by Chamberlain 
(‘98) (fig. rr). Indications of amitotic division may be some- 
times seen in the ventral canal nucleus in unfertilized archegonia 
(fig. 173), but such cases are rare. The development of the 
ventral canal nucleus in fertilized archegonia is not the exception, 
but the rule. In almost all cases in which there is a proembryo 
present there are to be found in the upper part of the archego- 
nium a varying number of nuclei of different sizes which have 
been derived from the ventral canal nucleus (figs. 175, 176). 
In some cases, as would naturally follow when the ventral canal 
cell is cut off far down the archegonium, the nuclei derived from 
it may occupy a position near the base, and consequently near~— 
the proembryo. fig. 7z8 is such a case. Here, the ventral 
canal nuclei are sharply distinguished from the nuclei of the 
embryo (only one of which is shown) by the entire absence of 
the starch sheath characteristic of the latter. The ventral canal 
nuclei are usually separated from the proembryo by a distinct 
area of disorganizing protoplasm, but they themselves seem to 
retain a part of the protoplasm at the tip of the archegonium 
which is not disorganized until much later (jig. 776). 
DEVELOPMENT OF THE FEMALE NUCLEUS. 
The female nucleus in its very young stages is shown in figs. 
65 and 89. It develops more rapidly than the ventral canal 
nucleus and goes through the peculiar changes of structure 
which have already been described in more or less detail by 
others. The chromosomes spin themselves out into a reticulum 
which is apparently often arranged in a spiral form (jig. 89). A. 
nucleolus begins to appear early. At the stage of fig. 89 the 
nucleus is not yet furnished with a distinct membrane, but in fg. 
go the wall has appeared. There is first seen at this stage a 
finely granular substance which has been called metaplasmic 
substance by Strasburger and some recent workers. From the 
subsequent behavior of this substance, it would be better described 
