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NOTES ON THE ABSOEPTION OF WATEE BY AEEIAL 
OEGANS OF PLANTS. 
By E. Makloth, Ph.D., M.A. 
(Eead July 21, 1909.) 
(With Plate XXVIII.) 
At the last meeting of this Society a paper was presented by Dr. 
Schonland "On the Absorption of Water by the Aerial Organs of some 
Succulents." From the results of certain experiments which the author 
had made with several species of plants, particularly with Mesembrian- 
themum harhatum, Anacampsews filamentosa, and Crassula cymosa, he 
came to the conclusion that *' Mesemhrianthemum harhatum and Anacamp- 
seros filamentosa cannot absorb any appreciable quantity of water through 
their aerial organs." 
It appears to me, however, that the experiments described by the 
author do not justify such a conclusion, especially as the conditions under 
which some of them were carried out are very different from those existing 
in nature. A twig of Anacampseros filamentosa, weighing 9*277 grammes, 
was kept in the laboratory for 7 days, when it weighed 8*672, having lost 
0*605 grammes of water — that means 0*086 per day. It was then 
immersed in water on 5 consecutive days for 15 minutes each time, and 
on the sixth day for 5 hours, and then found to weigh 9*011, having 
gained since the last weighing 0*339 grammes. 
The author considers that the gain is evidently due to the absorption 
of water by the long dead hairs and not by the leaves themselves. This 
gain is readily acquired, but also readily parted with." The author, how- 
ever, takes no notice of the loss, which the twig must have experienced 
during the time it was not immersed. As this time amounts to 5f days, 
and as the transpiration of the twig caused a daily loss of 0*086, the total 
loss during the period of the experiment from this source would have 
been 0*4:94:, giving a total absorption of 0*833, acquired during 6J hours of 
immersion, while in nature the plant would have been able to continue the 
absorption, at certain times of the year when dew is a regular occurrence 
every night, for at least 60 hours during that period. As the quantity of 
water absorbed amounts to 0*833 grammes, or, roughly speaking, 16 drops, 
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