532 Wo rsdell,— Observations on the Vascular 
the dorsal side of the seminiferous scale, and lie at equal 
distances apart. Somewhat higher up they die out, after 
gradually dwindling in size, and no bundles enter the short, 
narrow, free tip of the seminiferous scale. 
In the lamina of the bract there are a number of small, 
parallel bundles, slightly curved into an arc. Each has two 
or three layers of centrifugal xylem, and a large and well- 
developed centripetal xylem> consisting, as seen in transverse 
section, of several large angular tracheides, of which the 
outermost are almost or quite as large as the whole of the 
centrifugal xylem. Many of those on the ventral side have 
numerous very small bordered pits on their transverse walls. 
Transfusion-tissue occurs at the sides of the bundle, but most 
of the tracheides are in the ventral position. In longitudinal 
section the centripetal xylem consists, on the inner side, of 
considerably elongated tracheides which are rather broad and 
have very fine reticulations, amongst which small pits with 
narrow borders and wide openings are scattered. Further 
out, the tracheides become shorter and wider and lose the 
reticulate thickenings, retaining only the small bordered pits. 
The tracheides resemble those in the leaf and seminiferous 
scale of A. Bidwillii, Hook. 
Arazicaria Bidwillii , Hook. 
In this plant the bundles of the bract and seminiferous 
scale arise quite independently from the central cylinder of the 
cone-axis, and at a wide vertical distance apart. Each of 
these bundles is a compound structure, being formed respec- 
tively of two bundles branching off from two distinct strands 
of the cylinder. This is well seen in tangential section of the 
cone. The subsequent division of the two bundles in the outer 
cortex appears to be the same as obtains in A. Cookii , R. Br. 
Sometimes, however, one or the other bundle appears to arise 
from a single strand of the cylinder. 
As in A. Cookii , R. Br., an oval ring of bundles enters the 
appendage from the axis. Of these, many of those belonging 
