Reproductive Structures in the Podocarpineae . 79 
archegonia are apical. They vary in number from two or three in § Stacky- 
carpus and Dacrydium to ten or more in certain species of Podocarpus, and 
are with rare exceptions quite distinct from one another and not grouped. 
The neck may be either a single-tiered rosette or an irregular group of 
cells. In § Eupodocarpns , and to some extent in Dacrydium , asteroids, or 
centres of radiating fibrils, occur in the young archegonium. A large basal 
vacuole is everywhere present, save in § S tacky carpus. 
9. At fertilization the male nucleus is about half the size of the female, 
to which it becomes closely appressed and is finally fused. In all forms 
but § Stackycarpus only the first sporophytic mitosis takes place in the 
position of the fertilized egg, and the two resultant nuclei drop to the 
bottom and divide into sixteen. Walls are now laid down and a proembryo 
results of three tiers : a terminal binucleate embryogenous cell, a suspensor 
tier, and a poorly developed rosette. In § Stackycarpus the first two sporo- 
phytic mitoses occur in the upper portion of the archegonium, and the four 
nuclei, dropping to the base, give rise to a proembryo of four tiers: a single 
terminal cell more or less protective in function and often sloughed off; 
a group of from eight to forty cells which will form the embryo ; a suspensor 
tier, and a rosette. 
10. The endosperm cells in all species become multinucleate about the 
time of fertilization. The embryo remains intact except in Dacrydium , 
where it usually buds or divides. At maturity the embryo is dicotyle- 
donous. 
11. The close resemblance of Podocarpus to the Abietineae in the 
development of the male and female gametophytes and the embryo, as well 
as in the anatomy of the staminate and ovulate strobili, warrants the hypo- 
thesis that the Podocarpineae have been derived from the Abietineae 
through forms somewhat resembling Podocarpus . Certain points of simi- 
larity between Podocarpineae and Araucarineae suggest that these two 
families may have both arisen from an ancient group, closely abietineous in 
affinity. The advantages of this hypothesis are that it is in harmony with 
the view that the Abietineae are the most ancient Conifers ; that it assigns 
a logical position to the Podocarpineae; that it accounts for the wide 
variation in the genus Podocarpus ; that it offers a reasonable explanation 
of the origin of the epimatium, and that it makes possible the construction 
of a natural classification for the Podocarpineae on the assumption that the 
family represents three or four main lines of ascent from its most primitive 
genus, Podocarpus. 
12. The striking resemblance in strobilar anatomy, in the structure of 
the female gametophyte, and in the development of the embryo, between 
Stackycarpus , a sub-genus of Podocarpus , and Cepkalotaxus , the most 
primitive genus of the Taxineae, suggests that the latter family has arisen 
from some ancient member of the Podocarpineae. The structure of the 
