246 Scientific Intelligence. 
g in these directions.” Indeed 
the one is just as satisfactory or unsatisfactory as the other. The 
terms “geotropism,” “heliotropism,” “apheliotropism” and the 
like, transverse or otherwise,—now a numerous brood,—are useful 
have an inherent power of growin 
virtue of an inherent tendency? This is substantially denied by 
opposing forces. It is unnecessary to enter into particulars of 
how this obviously might produce the effect: for the result of Mr. 
Francis Darwin’s experiments is a clear disproof of DeVries 
h 
ve, its leaves will be horizontal. Let the plant be now 
made to rotate on a klinostat [so slowly that no centrifugal effect 
will be produced, but rapidly enough to destroy all geotropic 
action| so that the axis of rotation coincides with the axis of the 
plant. And let the direction of the incident rays of light be par- 
i 
geotropism being destroyed by the aah oy the balance cannot 
be maintained.” The experiments, varied in many ways, and wit 
arrangements to eliminate epinastic and hyponastie tendencies, 
plainly bring out the conclusion “that the power which leave 
