24 BOTANICAL GAZETTE [JULY 
the stage in fig. 62, is larger than the cells of adjoining tissue, 
but does not differ from them in structure. There is an abundant 
peripheral reticulum, staining blue throughout with gentian 
violet, and a nucleolus of compound structure, such as was found 
in the initial cell nucleus. In place of the single nucleolus there 
is frequently present a central group of quite distinct granules 
(fig. 63). All stages can be found between the distinct granules 
and the single compound structure formed by their fusion. From 
the nucleolus, or from the separate granules, linin threads extend 
which place the nucleolar matter in direct connection with the 
reticulum of the nucleus, and this I believe to be a constant 
character in nucleoli of chromatin material. That this nucleolus 
is largely composed of chromatin is shown by its subsequent 
behavior. As already mentioned, the nucleolar structure is the 
same in the prothallial cells and jacket cells, with the exception 
that in these the central or nucleolar collection of chromatin is 
quite inconstant in amount, the size of the nucleolus varying in 
proportion as the red-staining granules of the reticulum are more 
or less abundant. 
The number of archegonia in a group varies greatly. fig. 64 
shows a longitudinal section through a group of at least thirty- 
four archegonia, ten appearing in a single section. This is a 
larger number than has been found in any other gymnosperm, 
with the exception of Sequoia. The number is generally from 
ten to twenty, but in poorly developed prothallia there may be 
only a half dozen or less. Fig. 65 is a cross section of a group 
of seventeen archegonia. 
The neck cell very soon after its formation divides by a 
longitudinal wall into two cells of about equal size. This division 
is followed usually by another in each cell at right angles to the 
first, to form a tier of four cells (fig. 9g). If the neck of the 
archegonium is crowded or flattened, the second division may 
occur in one or both of the two first-formed cells (fig. 93). As 
the archegonium reaches maturity, the nuclei of the neck cells 
generally divide again, and walls may or may not be formed 
succeeding this division. The walls when formed are very irregu- 
lar in position. They are frequently somewhat inclined and 
