248 Browne.—A Second Contribution to our Knowledge of the 
of the lowest whorl enters the cortex from a rather small but quite 
normal sporangiophore, possessing spores normal in appearance, and dies 
out opposite to but without reaching a strand that gives rise to no trace in 
this whorl. All these abortive traces of the lowest whorl die out rather 
less than half-way through the cortex. In the twelfth whorl the sporangio¬ 
phore penetrated by the second trace in the reconstruction possesses another 
trace that dies out about one-third of the way through the cortex; in the 
sporangiophore this trace lies close to the second trace, but passing inwards 
and downwards into the axis it undergoes torsion to the reader’s left until, 
when it dies out, the distance between it and the second trace is twice what 
it was midway in the sporangiophore. This bifascicular sporangiophore 
seems not merely to be unusually large, as were the bifascicular sporangio- 
phores with one abortive trace of the lowest whorl, but to represent two 
fused sporangiophores. This is borne out by its greater size relatively to 
its neighbours, by the marked divergence of the two traces as they pass 
inwards, and by the fact that independent parenchymatous meshes arise above 
each of them. 
In Cone C of E. limosum I observed one case of one of the two strands 
of a bifascicular sporangiophore dying out in the cortex. This strand was 
relatively small, and its xylem died out almost in contact with the axial 
xylem, while it appeared as though the phloem of the trace actually joined 
on to that of the axial stele. 
It would be natural to suppose that the dying out of the traces in the 
cortex, which is so marked a feature of the lowest whorl of Cone A, might 
result from a diminution in the size of the stele relatively to that of the 
area of distribution of the sporangiophores, viz. to the circumference of 
the axis of the cone. But the reverse is the case; from the appended 
table it can be seen that compared with the circumference of the stem the 
stele is larger in the lowest whorl. 
Number of whorl . 
Circumference of stele. 
Circumference of axis. 
1 
14*25 mm. 
17*85 mm. 
4 
13*6 mm. 
18*91 mm. 
8 
12 mm. 
17*56 mm. 
12 
8 mm. 
13*07 mm. 
17 
i*4 mm. 
5*85 mm. 
Thickness of the Cortex in the Cone. 
The thickness of the cortex varies somewhat at the same level; it 
varies very greatly at different levels. It is not only relatively but actually 
narrower in the lowest whorls of the cone. The thickness of the cortex 
and that of the stele are given in the appended table for five selected whorls of 
Cone A, numbered from below upwards. This narrowness of the cortex at 
the base of the cone was a marked feature of all cones of E. maximum that 
I examined. 
