416 BOTANICAL GAZETTE [DECEMBER 
stant. This short period of development necessitated that all 
observations on one plant should be made within 36 hours. 
In those experiments which required that the plant be held in a 
horizontal position, the tumbler containing the toadstool was sup- 
ported firmly on a wooden block by a band of tin nailed securely to 
each side of the block (figs. 3, 4). A slender insect pin was placed in 
Fic. 3.—A. phalloides, in which supra-curvature has been neutralized. 
the center of each toadstool as a continuation of the axis of the stipe 
(also shown in the figures). This pointer made it possible to measure 
the amount of curvature accurately. After being collected and 
planted, each specimen was left in the normal position long enough 
to counteract any stimulation received during its transference and 
then it was placed on its side in the dark chamber. 
Usually the pileus does not become fully extended until after the 
