2 28 South and Compton. 
Stangeria 1 . In the fertile region of the axis centripetal wood dies 
out completely. 
In the cortex of the base of the peduncle small bundles 
are found, as in Stangeria : these are sometimes collateral (Fig. 
39), but irregularly orientated; frequently they are of concentric 
structure, the protoxylem being central, and secondary growth 
proceeding radially to a small extent all round (Fig. 40). In some 
a tendency to divide into two is noticeable. Scott is of opinion 
that the similar bundles in the peduncle of Stangeria are vestiges 
of the traces of missing leaf structures: this would appear to be 
also true of Dioon, as suggested by Matte 3 . 
III. —5 porophy II s. 
The quantity and distribution of the centripetal xylem in the 
male and female sporophylls has been determined by Worsdell 3 ; 
our own observations exactly agree with his description. Stomata 
are thinly scattered over the surface of the broad part of the male 
and female sporophylls, and open into the usual air-chambers. 
The functions of these are probably rather those of transpiration 
and respiration than of assimilation, since the cuticle is of con¬ 
siderable thickness, and very few chloroplasts are present. The 
presence of stomata here furnishes no argument for either view 
as to the nature of the sporophylls, since they are known to arise 
independently on many different aerial organs. 
IV. — Roots. 
The roots arise adventitiously from the base of the stem, three 
or four of them being large and profusely branched. The smaller 
roots, which are long and but little branched, are covered with 
small nodules strongly resembling those found in the Leguminosae; 
these occur either singly or to the number of four or five in a 
clump. 
All the roots are diarch and contain a large amount of secondary 
tissue. Here and there in the cortex a considerable number of 
stone cells occur. The external layers are corky and are developed 
from the usual phellogen. 
The nodules consist of parenchymatous cells, frequently con¬ 
taining crystals of various kinds and deposits of tannin. It is 
1 Scott, loc. cit., pi. XX., fig. 3. 
8 Recherches sur l’appareil libero-ligneux des Cycadacees, Caen, 
p. 115. 
a Ann. Bot. XII., p. 221 et seq., 1898. 
