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the Sporophylls of the Cycadaceae . 
concentric structure of those occurring in the sporophyll 
below the insertion of the sporangium and in the base of the 
latter is not entirely due to the radial symmetry of the 
sporangium which they supply. 
Encephalartos villosus, Lehm. 
Male Sporophyll. In the winged stalk is a row of bundles, 
of which the one on either side situated between the wing 
and the central region is the largest, and has a large amount 
of centrifugal xylem ; a certain small amount of centripetal 
xylem occurs at the sides of the bundle and is continuous 
with the centrifugal portion. The smaller bundles in the rest 
of the stalk have also very conspicuous centrifugal xylem of 
fairly large elements. 
Female Sporophyll. The axis of the cone to which these 
sporophylls were attached was not available for investigation, 
so that the course of the bundles therein could not be traced. 
The sporophylls are the largest of any in the order except 
those of Cycas. Their vascular system is, consequently, very 
well developed, and much resembles that of Cycas. As in 
that genus, the bundles have a large amount of centrifugal 
xylem, and many possess besides a considerable quantity 
of centripetal xylem, though others have less of the latter 
or even none at all. As in Cycas also, there are inverted 
strands on the dorsal side of many of the bundles, some 
of which have a small amount of centripetal xylem, while 
others have none ; most, if not all, appear to have protoxylem ; 
two strands placed back to back may be of equal size. But 
the bundles have a very irregular arrangement, being orientated 
and grouped in all kinds of ways, resembling somewhat the 
arrangement of the bundles in the basal region of the peduncle 
in Stangeria. At each side of the stalk there is an aggregation 
of bundles in close proximity and with variously orientated 
parts ; these are the strands which supply the sporangium ; 
the other bundles are smaller. In shape the bundles of the 
sporophyll are rounded and often very much curved, so as to 
