CHAP. VII. 



SLEEP OF LEAVES. 



329 



more than 90, so as to assume at night their vertical position. 

 On the first day the leaflet simply moved np and down ; on tUa 



Fig. 131. 



second day it plainly circumnutated between 8 A.M. and 4.30 P.M. 

 after which hour the great evening fall commenced. 



