456 BOTANICAL GAZETTE [JUNE 
from the node; but the central cavity is much narrowed in the 
nodal region, and the stele itself decreases somewhat in width, as 
is well seen in longitudinal sections. Sometimes no branches 
are initiated at these nodes, but in other cases one or two branches 
may be initiated, even at the uppermost vegetative node. As 
we approach the node the lateral bands of metaxylem of each 
bundle become united, as in the bundles of the large node already 
described. The bundles, at the corresponding heights, have 
much the appearance of those shown in fig. 1, stages 1-3, except 
that by the time we reach stage 3 the carinal canal is being replaced 
by a group of slightly disorganized tracheids. The median tooth 
of xylem seen in stage 4 of 
fig. 1 is not developed, 
although in some of the bun- 
dles the crossbar is slightly 
thicker in its median region. 
As in the larger axis, the cross- 
bar is separated from the 
carinal canal by two or three 
Fic. 6.—Stages 1 and 2; these stages show piece gerne sg 
appearance of bundles of small cone-bearing of the protoxylem elements 
branch of E. gigantewm at levels of node cor- Pass Out very g radually, 
responding to those shown for bundles of carrying with them such of 
pe highly canié, Jes 8 of figs. rand 2; the metaxylem elements ofthe 
crossbar as lie outside them. 
The same f sheath is formed for the passing out of the 
protoxylem. This sheath, which is relatively wide and conspicuous, 
is here directed obliquely upward, since the protoxylem, which 
lies in it, passes very slowly through the bundle. As there is here 
no median tooth of metaxylem, the metaxylem of the trace is more 
deeply situated in the bundle and nearer to the protoxylem, so 
that the protoxylem and metaxylem of the trace form, in most 0 
their course through the bundle, a single, radially elongated mass 
of similarly oriented tracheids. This stage is shown in fig. 6, 
stage 1, a stage corresponding more or less with stage 7 of fig. 1. 
While passing through the bundle, the metaxylem of the trace 
remains in contact at its outer end with the nodal xylem of the 
1 
