Stiles. — The Podocarpeae. 477 
they stand out distinctly on the outside of the woody integument after 
removal of the softer epimatium. 
The ovule of Podocarpus nagi has thus an exceedingly complicated 
structure, both as regards the differentiation of the seed-coat into four layers, 
and as regards the vascular system. Everything goes to show that this is 
a derived and not a primitive condition. The vascular system is extremely 
unlike that in the ovule of any other genus of Gymnosperms, but can be 
compared with that of Podocarpus macrophyllus . It is more complicated 
than in that species, but the ground-plan is the same, and the further 
development is no doubt connected with the large size of the seed. Further 
evidence in support of the condition being a derived one is found in the 
greater extent of fusion between the parts ; here the integument and 
epimatium are scarcely free from one another, while the megasporophyll 
is fused for part of its length with the ovular stalk. 
It is possible that this is the species vaguely described by Favre 1 under 
the name of P. chinensis . It has been suggested that this species might throw 
light on the homology of the vascular system of the ovule of Podocarpus 
with that of other Gymnospermous ovules , 2 Whether this be that species or 
not it furnishes additional evidence to that already advanced in the course of 
this section of the present paper, that the vascular system of the ovule of 
Podocarpus is not homologous with that of the ovules of the older Gymno- 
sperms described by various writers. It would seem that the ovular 
structure in the Podocarpeae has been evolved within the group, and it is in 
the genus which on general grounds one would consider the least primitive 
that one finds the most complex development. 
ix. Female Gametophyte. 
It is with regard to the female gametophyte and embryology that the 
greatest gap in our knowledge of the Podocarpeae occurs. Of the female 
gametophyte of Pherosphaera we know nothing ; in the case of Saxegotkaea, 
Microcachrys, and Dacrydium our knowledge is limited to a few isolated 
observations on the megaspore membrane . 3 In Phyllocladus and Podo- 
carpus a general outline of the gametophytic history is known in one species 
of each genus (Pk. sp. and P. coriaceus ). Owing to the kindness of 
Dr. M. C. Stopes and Mr. Saxton I have been enabled to examine gameto- 
phytic material of two species of the Eupodocarpus section of Podocarpus 
(P. macrophyllus and P. latifolius ), and one species of the section Nageia 
(P. nagi). The earliest stages were found in ovules of P. latifolius. The 
megaspore increases in size, and its nucleus divides, so that the free nuclei 
1 Favre (’65), p. 379. 2 Brooks and Stiles ('10), p. 315. 
3 Since this paper was written the writer has published a few facts relating to the Gametophytes 
of Dacrydium. See Stiles (’ll). 
