240 Jeffrey and Torrey . — Transitional Herbaceous Dicotyledons. 
aspect of the woody cylinder in a segment occupied by a foliar trace. The 
relations of the ray to the trace can be clearly seen and also the fact that 
the foliar trace turns somewhat abruptly radially outwards at its upper 
extremity. In the diagram to the right the topographical relations 
of the foliar trace in a more woody herbacous axis are shown, in the 
region of the node. To the left the foliar trace is seen only in transverse 
section in the tangential plane, since its vertical portion is buried deeply 
under the parenchyma of the foliar ray. In the lower region the massive 
foliar ray assumes the divided condition, which is present from the first in 
thin axes, below the node. The transverse view of the stem shows the 
large foliar gap so characteristic of the herbaceous type, whether of soft or 
woody texture. The right side of the figure under discussion shows the 
radial aspect of the foliar trace and of its related foliar ray. The trace in 
Text-fig. 3. Diagram of the topographical relations of leaf-trace and foliar ray in three dimen- 
sions. Left, a more delicate herbaceous stem. Right, a stem of more woody development. 
* f 
its vertical course is buried below under the central tongue of xylem, 
bifurcating the foliar ray in its lower portion. Higher up the leaf-trace 
comes to lie under the tangential portion of the foliar ray, which is not 
present in the more slender cylinder represented in the left-hand item of the 
diagram. In its uppermost course the leaf-trace passes rapidly outwards, 
and in this region is completely surrounded by storage tissue. 
Text-fig. 4 presents in its three items the general topography of thick 
and thin axes of the same somewhat woody aerial stem and of the more 
parenchymatous subterranean stem of a herbaceous perennial. A and B 
are constructed from thick and thin aerial stems of X ’ author hiza. In 
C appears the rhizome of a species of Actaea . The illustration in the last 
instance shows also the topography of the attached roots and their 
corresponding rootlets. Beginning with A, we have a stem three years 
old, shown in the transverse section in the region of an upper node. Below 
is the superficial view of another node. From this part of the diagram it is 
