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tents, which passes out into the spaces between them, and they contract 

 with the result that the leaf stalk curves in that direction which may be 

 upward or downward according to the location of the pulvinus. In a 

 few minutes after a pulvinus has curved in this manner, the cells which 

 have contracted begin to reabsorb water and finally regain their former 

 size with the result that the leaf is in its original position in fifteen to 

 twenty- five minutes after the stimulus was applied to the plant. It is 

 then capable of repeating its former action. 



Another movement, the object of which is unknown to us, is afforded 

 by the " Telegraph Plant" (Desmodium gyrans) which is to be found in 

 Jamaica. I have recently had the opportunity of examining several fine 

 specimens in the Castleton Gardens, and am informed that it is also grown 

 in the Hope Gardens. The general aspect of the plant is shown in Figure 6. 



Fig. 6. Desmodium gyrans. A. Normal position ol leaves. B. Leaves during darkness. 



