438 Browne.— A Fourth Contribution to our Knowledge of 
be brought into relation with the fact that whereas the stele has diminished 
in width the whorl contains one member more than the whorl below. 
The traces of the sporangiophores in this species are very small. 3 
When passing through the cortex they usually consist, as seen in trans- 
verse section, of five to nine tracheides. In the stalk the vascular strand 
remains slender until close to the peltate head, where, before it divides into 
radiating branches, the tracheides increase considerably in number. In 
mature cones the lower sporangiophores are often markedly reflexed, but the 
traces passing through the cortex are not deflected downwards, or only very 
slightly so towards its outer edge. The traces, other than those of the lowest 
whorls, pass obliquely outwards and upwards, though all the traces show a 
tendency to be slightly ‘ bowed ’ near their point of departure from the axial 
stele. Cases in which the trace of a sporangiophore is prematurely divided, 
so that two separate bundles enter a sporangiophore, single in nature, are not 
uncommon in this species (e. g. the traces of the first sporangiophore of the 
fourth and of the fifth sporangiophore of the eighth whorl of Cone A ; those 
of the tenth sporangiophore of the second, of the eighth sporangiophore of 
the fourth, and of the seventh sporangiophore of the ninth whorl of Cone B). 
In other cases the trace, though not bifascicular at its origin, arises deeply 
lobed and divides in the cortex or in the proximal part of the sporangio- 
phore (e. g. the thirteenth trace of the seventh and the first trace of the ninth 
whorl of Cone a) (cf. p. 454). 
In the reconstruction of the stele of Cone B a small white cross may be 
seen at the level of the second whorl. The third sporangiophore of this 
whorl is hardly, if at all, wider than its neighbours ; but it is traversed 
by two independent, approximated strands. One of these is the third trace 
of this whorl as shown in the reconstruction ; the other strand dies out 
in the cortex without reaching the axial stele, and the white cross marks the 
level at which and the radius on which its last tracheide dies out. In Cone A 
one of the strands passes through the level of the third whorl without giving- 
off a trace. The tracheides of the vascular supply of the sporangiophore 
opposite this strand pass inwards until they come into contact with the 
phloem of the axis, but die out without joining on to the tracheides of 
the axial bundle. The phloem of the sporangiophore is continuous with 
that of the axis. Similar variations from the normal have, it will be 
remembered, been observed in E. maximum (Browne ( 2 ), pp. 247-8). 
In E. debile the sporangiophores have short, relatively wide stalks. 
Varying degrees of concrescence are not uncommon (e. g. the fourth and 
fifth sporangiophores of the eighth whorl of Cone A ; the fifth and sixth 
sporangiophores of the third whorl of Cone C ; the first and second 
sporangiophores of the fourth whorl of Cone D, and the fifth and sixth 
1 In the reconstructions of the stele it has been necessary, for the sake of clearness, slightly to 
exaggerate the size of the traces of the sporangiophores. 
