324 EEY. G. HEN SLOW ON THE ABSORPTION OF BAIN 



tion-dew" to one, the upper or the under, surface of a leaf alone 

 as required, or else to both surfaces at once, as it is in nature. 



A large series of ver y various and freshly gathered leaves was 

 experimented upon, the general result entirely corroborating 

 previous conclusions. The loss per cent, was almost invariably 

 less when the lower side only was covered with dew — which shows 

 that absorption of dew by that surface is more readily effected 

 than by the upper. !Such, too, was the case, it will be remem- 

 bered, with water. 



The certain inference that we may draw is that dew (in nature) 

 is absorbed from below to supply the transpiration from above. 



Another series of some forty specimens consisted of leaves 

 which were left three hours to become flaccid. They were then 

 weighed ; the loss per cent, from the original weight when freshly 

 gathered was calculated. They were then treated with imitation- 

 dew, there being three examples of each species ; one had dew on 

 the upper surface, another on the lower, the third on both sides. 

 In more than half of them they gained weight after having been 

 left to dry ; the remainder had lost a very small fraction per cent. 

 This was due to the fact that they had become quite dry some 

 time before being reweighed ; hence they had again begun to lose 

 weight once more by transpiration. 



Hence this experiment entirely corroborated the one men- 

 tioned above of the absorption of actual dew by slightly * wilted " 

 leaves. 



9. On the Nourishment of Plants rooted in Pots ly aid of 



their Leaves and green Internodes alone. 



A small healthy plant of Mimttlus moschatus bearing three 

 shoots was growing in a pot. I ceased to water it on June 4th, 

 1878. By the 8th the shoots showed signs of wilting; so I now 

 placed the apices of two shoots only in water. On the 11th the 

 leaves on the third and exposed shoot had all withered ; but the 

 small buds in the axils of the lowest pair of leaves but one 

 remained vigorous, being about half an inch long. The smaller 

 buds, a quarter of an inch long, were in the axils of the next 

 pair of leaves. Lastly, the terminal bud and pair of leaves were 

 quite fresh and green. 



On the two stems which had their apices in water, the lowest 

 leaves (in air) were more or less withered by July 2nd. The 

 apex of the shoot in air and all its buds were now beginning to 





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