378 BOTANICAL GAZETTE [MAY 
tively into American botanical literature through his Botanical Text- 
book. Inhis Structural Botany, as late as 1879, he affirms that “this 
theoretical conception of the organic composition of the plant is 
practically important to the correct understanding of morphological 
botany.” From this source probably most of us of this generation 
derived the idea and believed it to be of value. 
It should be observed that the phyton or phytomer of Gray was a 
single node and internode with its leaf or leaves. No account what- 
ever was taken of the root, which was looked upon as, normally, a 
mere appendage of the lowest phyton, the like of which other phytons 
were capable of producing. It is scarcely necessary to say that no one 
who now considers the origin of the primary root can look upon it as 
morphologically an outgrowth of the shoot, and Gray’s phyton has 
been abandoned just as Gaudichaud’s was. 
PROFESSOR Bai.ey has felt it necessary to remodel the definition 
yet again. To him it is “that asexual portion of any plant which is 
capable of reproducing itself.”? Now no one is more familiar than 
Professor Bailey with the multifarious ways in which plants are propa 
gated by the gardener, and we must understand from these words that 
a leaf-fragment of begonia or a root-cutting of an aspen constitute 4 
phyton. Surely in no possible sense can these be considered as mor- 
phologically equivalent parts. Thus, beginning as an anatomical 
concept, the phyton has lost even an appearance of morphological sig- 
nificance. Let us then examine it as a physiological concept in the 
light of Professor Bailey’s explanations. 
In the preface already quoted, he says: ‘‘the phyton is simply — 
unit of asexual propagation as the seed is of sexual propagation.” 
This. mystifies us, though we have not failed to consider Mébius’ con- 
trast between Keime and Knospen, as admonished (Post, p- 385)- The 
_ only viable structure that one finds in the seed i is the embryo, usually 
with a well developed shoot consisting of a stem with a leaf or leaves, 
and a root. Yet we must understand that this embryo is nota phytoP 
in Professor Bailey’s sense, though it “reproduces ” itself precisely as a 
cutting would! 
ae See And, finally, we are told that, were it not for its various meanings, : 
_ “the word bud might be substituted for phyton.” (Now as a bud is 
: merely an undeveloped shoot, it would seem that this is not far Bs 
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