58 
Sinnott . — The Morphology of the 
The archegonia are from five to twelve in number, and occur in a circle 
around the apex of the gametophyte, but are never directly adjacent to one 
another (PI. VI, Fig. is). Each arises from a superficial cell which divides 
periclinically into primary neck-cell and primary central cells. The latter, 
which rapidly becomes elongated, has at first a very thin and foam-like 
contents filled with many small vacuoles, but no structures comparable 
to the ‘ asteroids ’ of the young central cell of Eupodocarpus were observable. 
One row of uninucleate, or binucleate, densely protoplasmic jacket cells be- 
comes differentiated around the archegonium. 
The small nucleus remains in the upper portion of the central cell until 
it has divided into egg and ventral canal nuclei, after which the egg nucleus 
drops to about the middle of the archegonium and becomes surrounded by 
a conspicuous layer of dense cytoplasm (PI. VI 1 1 , Fig. 34). The ventral canal 
nucleus, even if it is always formed, must usually go to pieces immediately. 
In the comparatively few cases where its presence could be determined, it was 
almost always as large as the egg nucleus itself, and the two were lying 
close together (Fig. 35). The many small vacuoles now coalesce into 
a single large basal one, and the cytoplasm of the egg becomes of uniform 
density throughout. Meanwhile the primary neck-cell has divided first 
anticlinally and then periclinally into a neck two or three tiers of cells in 
height. The endosperm grows up over the archegonia to such an extent as 
to leave the neck at the bottom of a small pit, or even sometimes to close 
it over entirely and prevent the access of a pollen-tube. 
In the details of fertilization, formation of the embryo, and history of the 
endosperm this species agrees almost entirely with Eupodocarpus (Figs. 36, 
37, and 38), but the embryo-sac is much wider and more nearly spherical, 
and its cells, beginning with a few towards the outside at the time of fer- 
tilization and increasing rapidly in number until they include almost all the 
endosperm, become completely filled with a mucilaginous contents (Fig. 38). 
The female gametophyte of Podocarpus dacrydioides differs chiefly from 
that of Eupodocarpus in the poorer development of spongy tissue and mega- 
spore membrane, in the absence of asteroids in the central cell, in the presence 
of a dense cytoplasmic sheath around the egg nucleus, and in the occurrence 
of mucilaginous contents in the endosperm cells. 
The sub-genus Stackycarpus, however, is distinct from the two pre- 
ceding groups in the structure and development of its female gametophyte 
and embryo. Podocarpus spicatus and P. ferrugineus , the only species ex- 
amined, were found to be very similar. 
The reproductive cycle covers a period of nearly eighteen months. 
Young female strobili appear early in October, and are pollinated two or 
three weeks later, but the embryo-sac, which attains considerable size, is not 
ready for fertilization until a year from the next January. Ripe fruit is 
produced in March. 
