REPRODUCTION AND DISPERSAL 



849 



a given color, such as blue, does not mean a preference for blue as such, but the asso- 

 ciation of nectar or pollen with that color. If a bee commences its activities on a 

 red flower, or on honey placed on a red paper, it is constant to red. In visiting 

 flowers, bees are constant not only to color, but also to form, flying from flower to 

 flower of the same species. This constancy to a given plant species for a certain 

 period is of great advantage to the plant, since it means a minimum waste of pollen. 

 It is equally of advantage to the bees, since the nectar or pollen is all of the same 

 quality, and since time and energy are saved in that exactly the same process is 

 repeated in each flower that is visited. The collapse of the color preference theory 

 is well shown in those cases in which different individuals of a given plant species 

 have flowers of different colors. In such species bees soon learn the essential like- 

 ness of the differently colored flowers, going from one color to another indifferently. 

 In other words, bees learn to ignore differences in color that are unaccompanied by 

 differences in nectar or pollen. Even if bees prove to be the only insects with a 



FIG. 1175. A colony of morning glories (Calystegia Soldanella) in dune sand; note 

 the striking contrast in tone between the flowers and the foliage, illustrating the possibility 

 of floral showiness even for color-blind insects ; New Zealand. From COCKAYNE. 



color sense, other insects certainly are able to appreciate differences in tone, as they 

 appear in a photographic print (fig. 1175), where whites and various colors come 

 into sharp contrast with the darkness of the foliage. Similarly, the prevalent white- 

 ness of nocturnal flowers makes them more conspicuous than would any pigment 

 color. 



Memory and instinct. When bees are taken to a new feeding ground, 

 their first flights are more or less misdirected and haphazard, resembling 



