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— save in what will presently be said, — in their relation to the 
lobes of the stigma. 
In order to see how the stigmas behaved toward the pollen of 
another origin, they were covered with that of Cassia florida, Morinda 
citrifolia, Begonia spec. div., Canna indica, Calonyction speciosum, 
Argyreia speciosa, Impatiens sultani, and of many other plants selected 
at will, whereby I found that whichsoever pollen might be used, the 
stigma always reopens within 10 to 15 minutes and thus behaves 
towards it in the same way as to the pollen from the shorter stamens. 
Only then when the pollen from the long stamens has been 
deposed on the stigma its lobes remain closed, no matter whether 
the stigma, in previous experiments, has already been dusted with 
the pollen of one or more other plants. 
I have now found of late that the irritable stigmas of Mimulus 
luteus display the same particularity with this difference, however, 
that the stizma of Mimulus always remains closed when dusted 
with its own pollen, no matter whether it is taken from the shorter 
or the longer anthers. 
Dusted with pollen of another origin the closing was always 
of short duration. Experiments were made with the pollen of Heme- 
rocallis fulva, Digitalis purpurea, Epilobium angustifolium, Tropaeo- 
lum majus, Torenia Fourniert, Pisum sativum, Datura Stramonium, 
Ononis spinosa, Maurandia erubescens, Lathyrus odoratus, Impatiens 
noli tangere, and other plants. 
A nearer examination of the stigmas of these two plants proves 
that the inner surface of the lips is highly irritable. The slightest 
touch makes them close directly. The outer surface, on the other 
hand, can bear considerable irritation without this causing the 
closing of the lobes. Few minutes, — in the mean a quarter of an 
hour, — after the lobes have closed in consequence of the stimulus, 
they open again and may then anew be induced to close in the 
same way. This can be repeated many times consecutively without 
the stigmas losing their irritability. The stimulus acts locally, that 
is, touching the inner surface of one of the lips does not affect the 
other but only makes the directly touched one move. If the style is 
cut through this changes nothing in the sensibility of the lobes, 
which are neither thereby brought to a temporary closing. Moreover, 
either of the lips may be cut away whoily or partly; the remaining 
portion continues irritable in the same degree. In consequence of the 
wound the stigma will shut, but within the determined time it is 
open again. . 
The closing of the lobes when pollen is deposed on them is exclus- 
