524 Simiott and Bailey . — The Significance of the ‘ Foliar Ray’ 
As a basis for their criticism of our position, Jeffrey and Torrey twice 
quote from our paper the following paragraph : 
‘ The fact, however, which militates most strongly against the validity 
of the hypothesis under discussion is that, in practically all many-bundled 
herbaceous stems, the interfascicular parenchyma is not subtended by tiny 
leaf-trace bundles, nor is the stem composed of presumably typical alter- 
nating large and small bundles, the latter being leaf-traces.’ 
This they evidently construe to mean a denial by us that the woody 
tissue confronting the entering leaf-trace may ever become converted into 
parenchyma, and to refute this supposed conclusion they cite a series of 
instances, drawn from the immediate region of the node, where such 
transformation does indeed take place. Upon this basis they further 
interpret our position as a denial of the presence in herbaceous types of so- 
called foliar rays, and they maintain that, on the contrary, these foliar rays 
not only occur in herbs, but. are actually an essential feature of the structure 
of all herbaceous stems. 
It is to be emphasized, in this connexion, that in our previous paper we 
did not deny that a transformation of xylem into parenchyma may occur in 
the nodal regions of aerial stems. The passage quoted by Jeffrey and 
Torrey, on the basis of which they attribute .such a denial to us, continues 
as follows : 
‘ On the contrary, all bundles in the aerial stem of a multifasciculate herb 
tend to be of the same general size, the leaf-traces in the stem usually grow- 
ing a little smaller as they near their point of departure. At this point, also, 
the segment of secondary wood which each of them subtends usually grows 
smaller too, and may become partially disintegrated into parenchyma! 
What we did deny is that the many-bundled condition existing 
throughout the aerial portion of the stem is due to a conversion into 
parenchyma of segments of the stem opposite the leaf-traces ; and that the 
interfascicular parenchyma in the long internodal portions of the stem is 
subtended by a xylem bundle. Both of these statements are amply borne 
out by the facts. Furthermore, it may be remarked in passing that the term 
4 foliar ray ’, in its present sense, has come into use since the publication of 
our paper. The criticism which has been directed against us on these points, 
and which forms the basis for the attack upon our position, is, therefore, 
quite fruitless, and is founded upon an inaccurate statement of our views. 
The significant portion of Jeffrey and Torrey’s work is their theory of 
the ‘ foliar storage ray ’, and of the part which it has played in the evolution 
of herbs. Obviously a clear conception of what is meant by 4 foliar ray ’ 
must be borne in mind if we are to discuss it. In their recent papers, 
Jeffrey and Torrey describe the foliar ray as a mass of storage parenchyma 
which has been developed in relation to the entering leaf-trace. It may 
confront the leaf-trace, flank it, or do both. In the more woody herbs, it 
