IS CONSPICUOUSNESS AN ADVANTAGE? 



blue forget-me-not and the yellow violet, as well as the saxi- 

 frages, in every conceivable color." Such a meadow in Alaska, 

 where the summers are equally short, is well described by 

 Burroughs : 



"Starred with flowers of every hue. 

 Gold and purple, white and blue; 

 Painted cup, anemone, 

 Jacob's ladder, fleur-de-lis. 

 Orchid, harebell, shooting-star. 

 Crane's-bill, lupine, seen afar; 

 Primrose, poppy, saxifrage. 

 Pictured type on Nature's page." 



According to a well-known principle of physics, each color 

 appears more brilliant in contrast with other hues than it 

 would if viewed alone. This can be easily shown by a simple 

 experiment, which any one can perform. Cut out two pieces 

 of red paper, each two inches square. Place one of the red 

 squares on a large sheet of green paper and the other red 

 square on a large sheet of red paper. The red square on the 

 green paper will appear so much more brilliant than the red 

 square on the red paper that the observer will have difficulty 

 in believing that they are identical in hue. (Figs. 101 and 102.) 



Is this beautiful and varied display of coloration by flowers 

 of no use.^ Has it no more significance than the vivid iri- 

 descent hues of minerals and precious stones "^ Is it merely an 

 incidental result .^^ To most observers it has long seemed self- 

 evident that conspicuousness is a manifest advantage. If 

 insects possess a well-developed sense of vision, bright colors 

 cannot fail to be of benefit to them as well as to flowers by en- 

 abling them easily to discover isolated blossoms and to econ- 

 omize time by being faithful to single plant species. No argu- 

 ment is needed to prove that such a correlation is desirable, 



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