4 BOTANICAL GAZETTE [JANUARY 
consider that the presence of foliar rays in aerial stems is rare, and 
that this supposed absence constitutes a weak point of the hypothe- 
sis of the derivation of the herbaceous type, which they .ascribe 
to the senior author of the present article. In a recent article 
WHITAKER (4) has demonstrated clearly the insecure basis of the 
assertion of Sinnott and BAILEy as to the absence of foliar rays 
in the aerial axis of the Compositae, perhaps the most important 
and certainly the most easily available group which is represented 
in temperate climates by typical herbs. One of us (4) has likewise 
recently discussed the anatomy of the flowering leafy stem of 
Helianthus, with similar conclusions. 
It will serve a useful purpose to begin the description of the 
herbaceous stem, from the aspects included in the present discussion, 
with a description of the aerial stem in certain common Compositae. 
Fig. 1 shows a transverse section of the stem of Aster novae-angliae, 
common in the eastern states. The lower region of the axis above 
ground is represented. To the left at the top of the figure can be 
seen a marked depression of the surface of the stem. ‘This corre- 
sponds to the median foliar ray of a leaf attached to the stem slightly 
above the plane of section. This ray is characterized not only by 
the depression it causes on the periphery of the stem, but also by the 
absence of vessels in its external region. Below this ray and on 
the left occurs another foliar ray, corresponding to one of the two 
lateral traces of the leaf under consideration. This ray is substan- 
tially like the one subtending the median trace, but is smaller 
in size and causes a less marked depression on the surface of the 
woody cylinder and on the periphery. The foliar ray of the right- 
hand lateral trace is about as far to the right of the median ray as 
the left ray is on the opposite side. It will be noted that the depres- 
sion in this case is very slight, and that the foliar ray is deeper 
radially and less broad than the other two similar structures. 
Since the traces do not always penetrate the stem at the same 
level, the rays which correspond to the three traces of the same leaf 
usually do not present the same appearance in details in a given 
section. An examination of the rest of the woody cylinder in 
fig. 1 shows that no foliar rays closely resembling the three under 
discussion can be distinguished. This results from the fact that 
