597 
Cone of Equisetum maximum , Lam. 
essentially similar results obtained from a study of the lowest whorls of 
Cones A, B, F, and G of E. maximum , I did not attempt to make a detailed 
study of the attachment of the xylem of the traces to the protoxylem of the 
stele throughout the whole of Cones A, B, and G, although this was done 
for Cone F. 
Before further considering these anomalous traces it may be well briefly 
to recall certain points as to the normal traces of the sporangiophores of 
E. maximum. As is usually the case in the genus the xylem of the traces of 
the sporangiophores is given off from the axial protoxylem. The traces of the 
lowest whorl, and to a less degree those of several of the succeeding whorls, 
are constantly deflected downwards as they pass outwards through the cortex. 
This deflexion is especially marked at maturity. In Cone B, which was 
mature, the average downward divergence of the traces of the lowest whorl 
was 997 iu, and in one case the extent of the downward deflexion reached 
1,500 ix. A similar downward divergence, often varying considerably in 
extent, is characteristic of anomalous as well as of normal traces in the 
lower region of the cone. 
As a result of the unequal downward deflexion of the traces in the 
cortex the difference of level between the traces at their insertion on the 
stele is often greater than the difference in level between the sporangiophores 
that they supply, and in some cases is sufficient to make it doubtful in 
examining reconstructions of the stele of the cone to which whorl certain 
traces belong. It is interesting to note that a similarly variable course is 
characteristic also of the protoxylem destined to the sporangiophore during 
its passage through the axial bundle. This feature is not shown in either 
of my reconstructions of the steles of Cones A and B of E. maximum , since 
they show the distribution of the xylem generally without indicating the 
course of the protoxylem (Browne, 1915, PI. XII and PI. XIII). The proto¬ 
xylem destined to pass out as the xylem of a trace may become detached 
from a (relatively) main axial protoxylem strand at the height at which it 
passes out of the bundle or considerably above or below this level. For 
example, taking the group of protoxylem strands that pass out as portions 
of the traces 7-13 of the lowest whorl of Cone A (see Browne, 1915, PI. 
XII), we find that the protoxylem supplying the seventh and eighth traces 
of the diagram is given off slightly above the point at which it makes its exit 
from the bundle. In other words, the tracheides of the trace are slightly 
deflected within the bundle. Those composing the protoxylem of the 
ninth and twelfth traces are more markedly deflected within the bundle, 
while those of the tenth and thirteenth traces pass outwards through the 
bundle in an upward direction, the former becoming free 750^ and the latter 
280/x higher up. The course of the protoxylem of the eleventh trace is 
highly suggestive. This trace shows the A anomaly, for the protoxylem of 
the incoming trace does not unite with that of the axis. Its elements run 
