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the Sporophylls of the Cycadaceae. 
tracheides lying some distance away, is always present ; in 
position and development it is the exact counterpart of that 
in the peduncle of Stangeria. It sometimes occurs opposite 
a gap between the bundles. 
Transfusion-tissue , of quite small tracheides with bordered 
pits or close reticulations, occurs in proximity to the centri- 
petal xylem both in a ventral and lateral position, and its 
derivation from this tissue is obvious. It is present in con- 
nexion with the cells containing dense protoplasmic contents 
surrounding the bundle ; where these cells are absent the 
transfusion-tissue is also no longer to be found. Some of 
the bundles are curved into a semi-concentric shape. On 
the dorsal side of nearly all the bundles are small strands 
with inverted orientation, their phloem being directly in 
contact with that of the main bundles. Each has an active 
cambium with (usually) a fair amount of xylem and phloem 
developed. Some have protoxylem ; other smaller ones 
have none, so that they are not all secondary. In this 
respect they resemble the similar strands observed in the 
peduncle of Ceratozamia . In one case, on the dorsal side 
of the protoxylem, i.e. on the side towards the periphery 
of the sporophyll, two tracheides occur which have evidently 
been formed by a cambium centrifugally, for regular radial 
rows of cells are seen on the dorsal side of these two tracheides. 
Also, on the ventral side of some of the tracheides of the 
centripetal xylem of the main strand, evidence of cambial 
divisions occurs such as I have also seen in the peduncle of 
Stangeria ; these were always observed in sister-cells of such 
tracheides lying on the inner (ventral) side of the latter 
towards the pith. Such division-walls were noticed nowhere 
else in the surrounding parenchyma-cells. 
Two strands are observed to pass off to a sporangium and 
enter it without previous branching. One of these is almost 
completely concentric in structure ; it has a large amount 
of secondary centrifugal xylem, and about three groups of 
protoxylem are observed around the inner margin of the 
latter. In the greater part of its contour the strand is 
