COLOR VISION 365 



regions of a spectrum. Whether the mechanical processes 

 associated with this discrimination are analogous to those 

 associated, with brightness or color vision in the human 

 being or neither is not known, but the processes in these 

 forms are undoubtedly very different from those associ- 

 ated with the reactions in simpler forms, e.g., in Amoeba 

 or plants. 



