IS COXSPICUOUSXESS AN ADVANTAGE? 



to the close of a long life. Had he been content to refute 

 Mueller's theory that insects exhibit color preferences, it is 

 probable that he would have met with little opposition; but 

 his sweeping denial of the value of conspicuousness in any 

 degree to flowers has not met with general acceptance and 

 can be easily shown to be incorrect. 



If the flowers of the common pear (Pyrus communis) be de- 

 prived of their petals, honey-bees will at once cease to visit 

 them for nectar, as is shown by the following observations. A 

 cluster of seven blossoms near the end of a branch was watched 

 for fifteen minutes and received eight visits from honey-bees. 

 The petals were now all removed and it was observed for a 

 second quarter of an hour. Though a number of bees flew 

 near by, it received not a single visit. During a third fifteen 

 minutes there were two visits, due in part to association, for 

 the bees came from other blossoms on the same tree, which had 

 proved the first source of attraction. 



Two other clusters of flowers, growing side by side, but nearer 

 the bole of the tree, consisting each of 8 flowers, were observed 

 for fifteen minutes, and 16 visits of honey-bees were noted. The 

 petals of one of these clusters were now removed. During 

 fifteen minutes the adjacent cluster, which still retained its 

 petals, received 11 visits, while not one was made to the cluster 

 without petals. In one instance a bee hovered over it but did 

 not alight. These results were very conclusive, and showed 

 that the bees were guided almost entirely by the presence of 

 the petals. 



Similar results were obtained from an experiment with two 

 groups of flowers belonging to the common borage (Borago 

 officinalis. Fig. *103.) They were distant apart about 6 

 inches; one contained 5 flowers; the other, which was at a little 

 higher elevation, contained 4 flowers. They were both watched 



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