530 Worsdell . — Observations on the Vascular 
seminiferous scale by a single layer of tangentially-elongated 
tannin-sacs. The tissue of the scale can be clearly seen 
extending as a narrow band round the outer side of the 
sporangium, and is perceived to be continuous with the inner 
portion of the scale (Fig. 6). The nucellus, throughout the 
greater part of its length, is quite separated from the integu- 
ment and easily falls out ; within it is the embryo-sac filled 
with clear and narrow-celled endosperm (Fig. 6). The 
nucellus is produced into a long black beak which protrudes 
beyond the integument and bends upwards externally to 
catch the pollen. It consists of contorted, elongated cells, 
like those of a stigma. Both bract and seminiferous scale are 
traversed throughout by great numbers of irregular stone-cells. 
A double system of small bundles, belonging both to the 
bract and the seminiferous scale, occurs in the region of the 
insertion of the sporangium, running below and parallel to the 
long axis of the latter (Fig. 6). Both systems occur through- 
out the sporophyll up to a short distance beyond the insertion 
of the sporangium. At four points, viz., right and left of the 
sporangium both at its base and tip, some of the bundles of 
the seminiferous scale fuse together into a single large bundle, 
having two or three layers of xylem and very conspicuous 
phloem ; at these points they may even assume a partially 
concentric structure, xylem and phloem occurring (as seen 
especially in one bundle) with inverted orientation, opposite 
the xylem of the large bundle. The reason for the increase in 
size of the bundles at these four points is not quite clear. 
These bundles lie slightly out of the row of small bundles of 
the seminiferous scale, for they are situated, two just above, 
and two just below, the insertion of the sporangium. Two or 
three of the bundles of the upper system, nearest the margin, 
perhaps die out. Immediately opposite the median portion of 
the sporangium there is a small blank space where no bundle 
occurs. The bundles of the seminiferous scale are, many of 
them, extremely small, some being quite rudimentary, with 
only an element or two of xylem. The bundles of the 
seminiferous scale appear to have a quite regular course from 
