Stiles . — T he Podocarpeae. 465 
is the greater one of its being essentially similar to the condition found by 
Thomson 1 in Agathis. As pointed out by the writer 2 and by Tison, 3 this 
nucellar expansion is similar to that occurring in Araucaria, but is much 
more prominent. Tison 4 reports that the nucellus is covered with a sticky 
secretion which no doubt keeps the pollen-grains attached to the 
nucellus during their germination. He finds that when the pollen is shed 
the sporophylls of the female cones on the same plant have already 
closed up. 
A rather remarkable phenomenon is the occurrence of cells towards 
the apex of the nucellus which have thickening bands on their walls 
and a somewhat tracheidal appearance. 5 Their function is obscure, but 
they may serve as water-storage reservoirs. 
After pollination the stigmatic expansion continues to grow for about 
two months. 6 Noren figures an ovule a year after pollination. The 
extruded part of the nucellus is still conspicuous at this late stage ; fertiliza- 
tion had not taken place in the ovule. 
The megaspore-mother-cell arises deep in the nucellus, at the level at 
which the nucellus and integument become free from one another. It is 
surrounded by ‘ spongy ’ tissue. 7 
Accounts of the vascular anatomy of the female fructification have 
been published by Thomson, Tison, and the writer. 8 The accounts agree 
in the main, but those of Tison and the writer differ in details. 
The axis of the cone contains a ring of endarch collateral vascular 
bundles with a resin canal outside each in the cortex (PI. XLVI, Fig. 7). 
Thomson found near the base of the cone ‘ a few centripetal elements 
associated with the bundles at the sides of the gap left by the exit of the 
megasporophyll trace ’. Similar elements were found, but rarely, in the 
upper part of the peduncle. 9 
A single bundle leaves the axis of the cone to supply the sporophyll. 
This bundle arises by the division of one of the bundles of the cone axis, so 
that the two bundles lie side by side in the ring. A little higher up the 
resin canal divides similarly. The sporophyll trace and its accompanying 
resin canal then bend upwards and outwards into the sporophyll. In the 
young condition observed by Thomson, the ovular supply is given off from 
the upper surface of the sporophyll bundle at the level of insertion of the 
integument. After the separation of the ovular supply from the sporophyll 
bundle, centripetal xylem-elements appear in connexion with the latter. 
1 Thomson (’07), p. 271. 2 Stiles (’08), p. 214. 
3 Tison (’09), p. 145. 4 Tison (’08), p. 137 ; (’09), p. 144. 
5 Nor&i (’08), p. 1 1 2, Fig. 16 ; Stiles (’08), p. 214. 6 Tison, 1. c. 
7 Noren (’08), p. 114. 
8 Stiles (’08), p. 215 ; Thomson (’09 2 ), p. 346 ; Tison (’09), p. 147. 
9 Thomson (’09 2 ), p. 348. 
