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upon them or if the plant is jarred, they sometimes remain quiet 
for a time or hurriedly scuttle out of the flower and take wing. 
I ean corroborate in every important detail the account given by 
Riley of the method of oviposition and pollination, either of 
which may occur first, while in a given flower both are usually 
repeated many times before the moth goes toa new one. The 
energetic manner in which the little insect works its head up and 
down*while depositing pollen in the stigmatic cavity, is very in- 
teresting, and cannot fail to convince a person who sees it that 
there is as much object in its work as in the nest-building of birds, 
or other so-called instinctive operations of the lower vertebates. 
To more effectually accomplish its mission, the moth usually 
pushes the pollen further into the cavity than its tentacles can 
reach, using its tongue for this purpose, and it is perhaps this 
action which led Riley to believe that it sips nectar from the 
stigma while engaged in the act of pollination. Once a pair of 
moths were seen to copulate in the flower, the union not lasting 
more than three or four seconds, the female actively running 
about the flower in the meantime, and immediately resuming the 
labor of oviposition on its completion, when the male flew to 
another flower. 
If what I have observed may serve to disprove any positive 
value of their nectar in the pollination of Vucca flowers, it only 
adds to the general interest of the subject ; for it shows that not 
only the act of collecting the pollen is performed voluntarily and 
without any food compensation, as stated by Riley, but also that, 
of transferring it to the stigma—a case without a parallel, so far 
as I know, among entomophilous flowers, if we exclude those 
witlr false nectaries; and I doubt if these are all fully under- 
stood. 
The student who wishes to look up the literature of the 
pollination of Yucca, will find an indication of the principal papers 
on the subject in Thompson’s catalogue of books and papers re- 
lating to the fertilization of flowers, in the English edition of 
Miiller’s Fertilization of Flowers, to which should be added: 
Meehan, Penn Monthly, 1876, 836; Bot. Gazette, iv., 242; 
Proc. Phila. Acad., 1880, 355; Amer. Agriculturist, 1872, 461; 
1873, 223; Miiller, Wechselbeziehungen, 39; Darwin, Cross and 
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