Hickling . — The Anatomy of Palaeostachya vera . 375 
tracheids, was situated just a little below the lower limit of the ‘ nodal 
disc.’ The secondary wood was here thickest, and gradually died out 
above and below, extending in the upward direction just about to the 
upper limit of the * disc/ I have diligently endeavoured to determine 
whether or not there is an alternation of bundles in the successive inter- 
nodes. No tangential section exists sufficiently perfect to determine 
whether the successive whorls of appendages are superposed or not. From 
an examination of the numerous sections which cut more or less transversely 
through the node, I feel little doubt that no regular pectination occurred, 
while, on the other hand, one or two sections show features which seem 
explicable only on the assumption that occasional communications (probably 
irregular) did occur between adjacent bundles. 
Vascular Supply of the Appendages . The course of the bundles which 
supply the bracts can only be traced with great difficulty, but it is evidently 
quite simple. Several of the bracts themselves show traces of quite a large 
xylem-bundle, and in the transverse section (Fig. 15) a single median 
bundle is clearly seen. There is no evidence in any case of more than 
a single bundle in the bract, though as Fig. 1 5 represents a section not far 
from the tip, it cannot be regarded as conclusive. The trace in the cortex 
is practically always lost, owing to the removal of the surrounding 
parenchyma, and for the same reason it is generally lost from the bract 
itself (see below, p. 378). A single section shows very imperfect macerated 
fragments of this bundle in the cortex, but its origin from the main bundle 
is fairly well seen in several cases (Fig. 20). It arises from the primary 
wood of that bundle just where the carinal canal is obliterated, and passes 
radially outwards and slightly upwards through the nodal secondary wood, 
which course was no doubt continued through the cortex till it curved 
downward into the bract. No gap is left in the main bundle, and as all 
the tracheids throughout the bract-bundle appear to be spiral or annular, 
it may be concluded that it received no contributions from the secondary 
wood. 
Sporangiophore Bundles. Since the course of these bundles is the main 
point which fixes the position of this cone in the Calamarian series, it is 
a fortunate circumstance that they are accompanied through the cortex by 
sclerized tissue, and so are completely preserved. Yet the totally un- 
expected nature of the course led to its remaining long undiscovered during 
the present investigation. The origin of the bundle is immediately above 
that of the bract-bundle ; i. e. they originate one above the other at 
the same node. But the sporangiophore bundle does not separate from the 
main bundle until it has ascended through almost exactly half the 
internode. It is then sharply reflexed, descends rapidly to the upper 
limit of the sclerized ‘ nodal disc,’ and sweeps horizontally across 
the upper part of this to the base of the sporangiophore. The great 
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