356 



HENRY LAURENS AND HENRY D. HOOKER, JR. 



that the stimulating influence of the white Hght, though of equal 

 radiant energy power, does not, or cannot, influence the organ- 

 isms. But in the regions of the spectrum of wave-lengths of less 

 stimulating effect, the influence of the white light reveals itself, 



TABLE 2 



The relative stimulating value of spectral lights of equal energy content as determined 

 from the relative rate of locomotion 



becoming relatively stronger and stronger, so that orientation 

 and locomotion toward the source of the spectral lights are pro- 

 gressively made less precise and retarded, with the result that 

 the ratio of the rate of locomotion to spectral light as compared 

 with the rate to white light becomes greater and greater. The 



