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RESEARCHES ON FUNGI 



Cb 



CL_ 



Ob 



V yv 



zS 



/ 



Cb 



oc 



2d 



B 



Fig. 59. — A diagram to illustrate the reaction of a fruit-body of Pilobolus Kleinii to 

 light coming from two equal sources at the same time. 



A, part of the wall of a dark chamber in which are two windows, a and b, 

 with their centres 4 cm. apart. Through these windows two beams of light 



