6 BOTANICAL GAZETTE [JANUARY 
proximity to the next superior node. In extremely slender her- 
baceous stems, on the other hand, by the thinning of the woody 
cylinder, the foliar ray radially external to the leaf trace is elimi- 
_ nated, and only the flanking portions of the ray on either side of 
the foliar trace in its upward vertical course in the stem can be 
distinguished. It follows that an alternation of foliar rays and stem 
bundles is extremely common in herbs which are transitional in 
their texture, but naturally does not occur in either extremely 
woody herbs or in those which are strikingly herbaceous. 
In fig. 6 is shown the foliar ray and its inwardly subtending 
leaf trace. The foliar trace may be recognized as radially disposed 
groups of vessels separated by equally radial bands of parenchyma. 
Externally the vessels give place to fibers and parenchyma, which 
constitute the external or confronting portion of the foliar ray. 
Lateral to the vascular leaf trace on either side can be distinguished 
the flanking portions of the foliar ray. It follows that a foliar 
ray may consist of parts flanking the leaf trace and separating it 
from the adjacent stem segments, as well as a region subtending the 
foliar strand externally. In thinner stems the latter portion 
progressively disappears, until only the flanking portions of the 
ray persist. This situation has recently been represented in 
diagram by WHITAKER. SINNOTT and Battery (6) have, however, 
quite failed to understand the situation. Since the genus Aséer is 
a somewhat woody herb the topography represented in figs. 2-5 
is usual in the upper region of the stem of various species. 
We may now pass to a more herbaceous illustration of the 
Compositae, namely Helianthus, which has already been used (4) 
to exemplify the anatomical conditions in regard to the topography 
of the foliar rays. Corresponding to its less woody structure is 
the fact that foliar rays possessing depth enough to subtend as 
well as flank the leaf trace are confined usually to the lower portions 
of the aerial stem. In the superior portion of the latter the leaf 
rays are purely flanking in their development, on account of the 
slender nature of the woody cylinder. Disregarding the latter 
condition for the moment, we may turn our attention to the lower 
region of the subaerial stem. Fig. 7 is a foliar ray from the 
base of the stem of Helianthus annuus. Obviously the continuity of 
the woody cylinder is broken by a strongly developed radial band 
