﻿BOTANICAL GAZETTE 



were conducted both out of doors and in the laboratory, with the 

 leaf right side up and upside down. In each case the effect of the 

 local withdrawal of water was the assumption of the xerofotic 



In additional experiments, branches of trees were cut away so 

 that shade leaves, in which no previous xerofotic movement had 

 been noted, were exposed to the full sun. In all such cases the 

 xerofotic position was soon taken. A burning-glass, used to intensify 



the action of the sun on leaflets which had been artificially shaded, 

 brought about a more rapid assumption of the xerofotic position. 



Both shade and xylol experiments were conducted upon the 

 con vol vulaceous Ipo moea Pes-caprae, growing on the strand of Taal 

 Volcano, Philippine Islands (figs. 6. 7, and 8). In this case the 

 clam-shaped simple leaf spread out under the dense shade of a 

 screen and spread out leaves folded nearly together soon after xylol 

 was applied to the upper part of the midrib. 



1. Xerofotic movements are paratonic movements, caused by 

 unequal drying effects in direct sunlight, manifested by an upward 

 bend in leaflets or a curling upward of the blade. Greater turgor 



