0 UME XL NUMBER 4 
MTANICAL (sAZETTE 
OCTOBER, 1905 
REGENERATION IN PLANTS. _ II.” 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY. 
XXITX. 
WILLIAM BURNETT MCCALLUM. 
(WITH NINE FIGURES) 
WOUND STIMULUS. 
Tue influence of the wound has been put forward many times, 
either as the direct cause, or as an important factor in regeneration. 
WIESNER (19) has suggested that between the wounded part 
and the new structure formed there is a direct causal connection, 
due to substances developing in the wounded cells and passing to 
other parts, there inciting the reversion of mature cells into the 
meristematic condition. GOEBEL (4, p. 204) also believes the 
wound stimulus to be a factor. KLEBS (9), on the other hand, 
rather discredits this idea and thinks that the wound in itself is of 
no Importance in regeneration. The possibility of the wound having 
a far teaching influence is not at all improbable, for many well-known 
fases of traumatropism show how cells may be affected at a distance 
from those actually concerned in the wound. Of the many experi- 
Ments to determine if such an influence is operating, only a few need 
s Mentioned, and in these cases only the results will be given. 
i. Was seen that with Phaseolus the removal of the stem above 
ag primordia is followed by the development of the latter. 
. femoval of the cotyledons, while causing wounds still closer to 
ie young bud, produces no such development; nor does the sever- 
_ 1g of the stem as close as possible below the primordia. Wounding 
. by cutting notches immediately above the primordia, as 
first paper was published in BoraNIcAL GAZETTE 40:97-120. 1905- 
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