55 
Reproductive S true tin' es in the Podocarpineae. 
multiply rapidly, come to lie against the wall, the centre of the gametophyte 
being filled by a large vacuole. For the immediately succeeding stages, in- 
formation is available only in the cases of P. Totara and P, Hallii. In these 
species the vacuolated sac becomes lined with hundreds of free nuclei before 
wall-formation begins. The first walls isolate each nucleus from its neigh- 
bours and leave it in a distinct compartment, but in free communication 
with the vacuole. The nucleus lies at the inner end of this compartment, 
and is connected by protoplasmic fibrils with the edges of the inwardly 
growing walls, which eventually meet at the axis of the gametophyte. The 
sac is thus filled with radiating tubular ‘ alveoli ’ which are rarely interrupted 
by transverse walls. The division of each alveolus into a row of cells, 
however, takes place rapidly after the cessation of centripetal growth, and 
the gametophyte thus becomes a body of thin-walled uninucleate cells 
arranged in rows radiating from its centre. The spongy tissue disintegrates 
as the embryo-sac reaches its full size, but a very well-developed megaspore 
membrane, thick basally but becoming thinner over the apex, is laid down 
around the gametophyte (PI. VI, Fig. 7). 
The history of the female gametophyte and embryo of Eupodocarpus 
from this point onward was studied in P. Totara , P. Hallii , and P. nivalis , 
and is practically identical in the three species. 
The archegonia appear soon after the sac is filled with tissue, and 
occur in an apical group of three to six (Fig. 7). As many as fourteen 
have been noted by Stiles in P. latifolius . They are arranged roughly 
in a circle, but are rarely or never grouped, always being separated from 
one another by one or more rows of cells. 
Each archegonium arises from a superficial cell, which soon divides 
periclinally into a primary neck-cell and a primary central cell. The neck- 
cell is unchanged for some time, but the central cell, growing rapidly, 
becomes much elongated, and is filled with thin, vacuolate contents. The 
nucleus remains at the upper end, just below the neck. No further changes 
take place until the archegonium reaches its full size, when three deeply 
staining centres of radiating protoplasmic strands appear in the central 
cell, one at the base, one near the middle, and one j ust below the nucleus at the 
apex (PI. VII, Fig. 27). Between the lowest two of these ‘ asteroids ’ arises 
a large vacuole. The primary neck-cell has meanwhile divided anticlinally 
or obliquely into an irregular group of cells. One row of jacket cells, 
distinguishable from the surrounding gametophyte tissue by their more 
dense contents and large nuclei, one or two in number, becomes differentiated 
around the central cell. 
The nucleus of the central cell now undergoes division into egg nucleus 
and ventral canal nucleus, and although the actual mitosis was not observed, 
the two small resulting nuclei were several times seen in the upper portion 
of the cell. The egg nucleus remains for only a very brief tinie in this 
