IS COXSPICUOUSNESS AN ADVANTAGE? 



then, does it happen that they so often visit indiscriminately 

 in our gardens the differently colored varieties of the same 

 species of flower, as the white, yellow, orange, red, and purple 

 varieties of Zinnia, or the red, white, blue, and purple varieties 

 of bachelor's-button (Centaurea cyanus) ? It is obvious that 

 the flowers belonging to each species are alike in shape, odor, 

 and nectar, and differ in hue alone. Under these circumstances 

 it is for the advantage of bees to pass freely from one color to 

 another, and this they speedily learn to do. 



Since bees are able to distinguish between different colors, 

 and cease to visit flowers as soon as the brightly colored floral 

 leaves are removed, and find a flower which contrasts sharply 

 in color with green foliage more quickly than one which is simi- 

 larly colored, conspicuousness is clearly a great advantage in 

 attracting insects. 



If, however, brightly colored flowers, as in the case of many 

 gaudy exotics of cultivation, are nectarless and yield little or 

 no pollen, bees soon learn that no food is to be obtained from 

 such blossoms, and remembering this, thereafter visit them 

 only occasionally. The large flowers of the cultivated purple 

 clematis (Clematis Jackmanni), for example, are nectarless and 

 odorless, but produce a small amount of pollen. Careful and 

 almost continuous observation showed that they were at times 

 visited by honey-bees and solitary bees, which gathered all of 

 the pollen. I inspected the flowers many times without find- 

 ing any insects, and a casual observer might easily conclude 

 that they were entirely neglected. After the pollen had been 

 removed there was no reason why insects should continue their 

 visits. 



For the purpose of learning whether the visits of bees could 

 not be induced in large numbers, I next placed on a few of the 

 flowers sugar-syrup, which is an odorless sweet liquid. Honey- 



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