454 
Stiles . — The Podocarpeae. 
this order. The leaf of Podocarpus nagi is about 6 centimetres long by 
2 centimetres wide, and often has as many as 40 veins. The superficial 
resemblance of the leaves of Nageia to those of species of Agathis has been 
frequently commented on, as well as the resemblance of both these types 
to the leaves of Cordaitcs. 
In Phyllocladus the true leaves are reduced to scales, being replaced 
functionally by phylloclades. 
In most of the species the leaves are arranged spirally on the axis, but 
in the Nageia section of Podocarpus , as well as in Microcachrys , Podocarpus 
vitiensis , and P. elongatus, a decussate or sub-decussate arrangement 
prevails. 
B. Internal Structure. 
The internal structure of the leaves of the following species has been 
examined : Saxegothaea conspicua , Microcachrys tctragona , Dacrydium 
cupressinum , D. Franklini , Podocarpus nagi , P. andinus , P. amarus , P. 
macrophyllus , P. elatus , P. polystachyus , P. salignus , P. Totara , P, elongatus. 
In addition accounts of the structure of the following species have already 
been published: Podocarpus chilinus 1 (= P. salignus , D. Don), P. nagi? 
P. neriifolius and P. falcatus? and P. spinulosusP The leaf of Micro- 
cachrys has been described by Thomson, 5 and its structure compared with 
that of the megasporophyll, a comparison which has brought out some 
interesting points. Observations on the leaves of Phyllocladus have been 
made by Mrs. Arber. 6 As well, there is the comparative account of the 
structure of the leaves of Saxegothaea and Podocarpus (in which the genus 
Dacrydium is included) by Bertrand. 7 A brief general account of the 
anatomy of the leaves in the Taxaceae is given by Pilger. 8 
From these accounts, and from investigations on the species mentioned 
above, it is evident that several types of leaf occur in the Podocarpeae. 
1. Perhaps the commonest type of leaf is that of Podocarpiis macro- 
phyllus (Text-Fig. 2, a). In this species the leaf is 5 or 6 centimetres long 
and about 7 millimetres broad. On each side of the xylem of the median 
vascular strand is found well-developed transfusion tissue (reticulate cells of 
Bertrand). From either side of this stretches to the margin of the leaf the 
accessory transfusion tissue of Worsdell (transfusion tissue of Bertrand and 
hydrostereome transversal of Bernard). Descriptions and figures of both 
transfusion tissue and accessory transfusion tissue are given by Worsdell 9 
and Bernard. 10 On the lower or phloem side of the vascular bundle occur 
three resin canals, one median with regard to the bundle, the other two, one 
1 Worsdell (’ 97 ), p. 310. 
3 Bernard, 1 . c , p. 275. 
6 Thomson (’ 09 2 ), p. 349. 
7 Bertrand ( 74 ). 
9 Worsdell (’ 97 ). 
2 Bernard (’ 04 ), pp. 268, 270. 
4 Brooks and Stiles (TO), p. 307. 
6 Robertson (’ 06 ), p- 260. 
8 Pilger (’ 03 ), p. 7. 
10 Bernard (’ 04 ), 
