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THE AMERICAN NATURALIST [Vol. XL V 



volvulus blossom had completely wilted and collapsed, 

 its noticeable color alone continued to invite inspection 

 by passing bees quite as often as the control blossoms 

 at (c). 



E.tpn iment No. 16.— July 28. Period of observation 

 one half hour, from 10 :1 5 to 10 :45 a.m. The three points 

 in the preceding experiment were used as follows: 



At («) a single cotton petal was placed on the 

 blossom of the preceding experiment, from which all 

 the petals had been removed. 



At (b) a single cotton petal was loosely pinned to a 

 stem. 



At (c) control. A normal cotton blossom pinned in a 

 conspicuous position. 



The blossom at (a) receives 8 inspections. 



The petal at (b) receives 9 inspections. 



The normal blossom at (c) receives 27 inspections 

 with no entrances. All visitors were Melissodes, except 

 a small bee which inspected (c). 



As the blossom at (c) was conspicuous from all sides, 

 the writer judged that this fact accounted for the much 

 greater number of inspections given this blossom, since 

 (a) and (b) were visible almost wholly from one side 

 only. In the next experiment this question was further 

 tested. 



Experiment No. 17.— July 28. Period of observation 

 one half hour, from 10:45 to 11:15 a.m. In this experi- 

 ment the only changes from the preceding consisted in 



