No. 542] 



COLOR SENSE OF THE HONEY-BEE 



101 



or honey on them was plainly visible at a considerable 

 distance. According to the reiterated statement of 

 Plateau all flowers might be as green as their leaves 

 without their pollination being compromised, and color 

 and form are of little consequence in comparison with 

 odor. But the experiments showed that color contrast is 

 of great value, and in these particular experiments indis- 

 pensable. If the leaves provided with an ample supply 

 of honey or syrup could not obtain a single visit under 

 the conditions described, where a large number of bees 

 were brought into their immediate vicinity, how little 

 chance there would be for an isolated plant with small 

 green flowers growing in a secluded location attracting 

 visitors ! But a bright-colored flower in the same locality 

 would be much more likely to gain the attention of pollin- 

 ating insects. 



On September 20, 1910, at 2:15 p.m., numerous black 

 bees were coming to the feeder for honey. At a distance 

 of three feet away I laid on the grass a bright yellow 

 flower of golden glow (Rudbeckia lucht'mtu) two inches in 

 diameter. On the opposite side of the feeder three feet 

 from its base, I laid the end of a spike of Amarantus 

 retroflexus about three inches long. The small, pale 

 green flowers are thickly crowded in panicled spikes. An 

 ample supply of honey was placed on both. In the course 

 of fifteen minutes there were 18 visits to the flower of 

 golden glow and only 8 to the Amarantus cluster. If a 

 bee flew to either object, but did not alight because of the 

 large number of bees already there, this was counted as a 

 visit. 



The bees were again accustomed to visit the feeder. 

 In the preceding experiment one of the objects had been 

 placed on the east side of the feeder and the other on the 

 west. Both the flower of the golden glow and the spike 

 of Amarantus were now laid side by side on the grass in 

 the sunshine three feet to the north of the feeder. There 

 was honey on both. In less than ten minutes there were 

 fifteen visits to the golden glow and only three to the 



