SPECIAL SENSES 



15 



light — that is, with their upper surfaces to the 

 window. Leaves and stems, therefore, show 



l-e/^'g^'t' pojitior) 



\ ^~ 1 2. 0^ pojiti 



OT). 



Fig. 3. — Day and night positions of the leaves of redbud 

 Cercis Canadensis). 



