254 BOTANICAL GAZETTE [OCTOBER 
The stalk of an isolated leaf without any piece of the stem is not 
capable of giving rise to any regeneration. Such a leaf will form 
adventitious roots and shoots in its notches very rapidly. 
All these facts make it appear as if the growth of the buds on a 
piece of the stem might have an inhibiting influence on the growth 
of the adventitious roots or shoots of the leaf. 
In order to estimate properly such an influence, an extensive 
series of experiments was made, in which leaves with a piece of 
stem attached were submersed with their tips in water, while the 
rest of the specimen was in moist air. In a number of stems both 
buds were removed (fig. 7), in another only the upper buds were 
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. 7 8 
Fics. 6-9 
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removed (fig. 8), while in the rest of the stems none of the buds were 
removed (fig.9). If the inhibiting effect of the stem were exclusively 
due to the growth of the buds on the stem, the latter should lose its 
inhibiting effect entirely if these buds were removed; and the leaf 
connected with such a ‘“‘debudded” stem should form adventitious 
roots or shoots as fast as a leaf without any stem. This was, 
however, not entirely the case. While a leaf connected with a 
‘“‘debudded”’ stem (fig. 7) formed as a rule its adventitious roots 
more quickly than a leaf with a normal stem (fig. 9), the leaves 
connected with the ‘‘debudded” stem formed their adventitious 
roots not quite so quickly as the completely isolated leaves 
fig. 6 
