240 THE AMERICAN NATURALIST. [VoL. XXXVI. 
honeybee prefers blue, violet, various shades of purple and red, 
to white and yellow, and avoids scarlet and lurid colors. 
6. The formation of pigments is effected by the chemical 
composition of the soil, by altitude or the intensity of light, by. 
latitude, and by the absence or presence of moisture, as well as 
other ecological forces. The particular coloration of flowers is 
largely a chemical problem. 
