MAIN RESEARCHES OF PLATEAU. 163 



searches. They confirm these all the more, since, advised by the criticisms, I have 

 endeavored to avoid everything that could lead to objections: it has been said that 

 the imitations employed were too few in number compared with the normal flowers; 

 this time I have used numerous examples and in several cases the numbers of the real 

 flowers and of the copies were essentially the same; it has been objected that I have 

 not tried the attraction of imitations completely isolated; I have now done this repeat- 

 edly; the erroneous objection has been made that my artificial flowers have been 

 nothing but gross imitations; I have continued to use only the most careful imitations 

 possible and have frequently employed the very same species utilized by my critics. 



"I can then only repeat the conclusions that I have formulated earlier, modifying 

 the words alone a little in order to avoid all ambiguity, and emphasizing the necessity 

 of good experimental conditions: 



"1. In much the greater number of cases insects pay no attention to artificial flowers 



of vivid color and frequently treat them merely as obstacles in their way. 

 "2. In the relatively small number of cases where they perceive the presence of the 



imitations, they usually show only a brief hesitation, which is revealed by a 



turn or a crochet before or around them. 

 "3. Insects never seek pollen or attempt to suck nectar in a flower truly artificial and 



containing no attractive material of any sort. 

 "4. The attractive influence of bright artificial colors can in consequence be regarded 



as nearly null. 



"However, if this laborious study has ended only in the demonstration of the accur- 

 acy of my earlier results, it has permitted what is perhaps more important, the dis- 

 covery of most of the errors committed by my opponents and the reasons why they 

 have believed in good faith in the actual attraction of artificial flowers. Such errors 

 are as follows: 



"A. To cover, conceal, cut or suppress in any manner the natural flowers and to 

 replace them with artificial ones. In this case, insects, and especially the 

 bees, not finding pollen or nectar where it was on former visits, fly in seeking 

 it about any object occupying the place or located near it. 



"B. To place artificial flowers near or among natural ones. Under such conditions it 

 happens occasionally . that insects which start by going directly to the real 

 flowers, in passing from one flower to another or in leaving, hesitate before 

 an artificial one as one sees them stop before faded flowers or even closed buds. 



"C. To make studies with artificial flowers in places where they have already been 

 performed with natural ones, since such places might have become habitually 

 visited by bees, for example. 



"D. Not to have taken into account the significant difference between a direct flight 

 and simple turns or crochets of inspection. 



"E. To disregard the well-known details of behavior, thus to forget that syrphids 

 may hover before any object whatsoever, that the muscids alight constantly 

 upon the most diverse surfaces, chiefly to expose themselves to the sun, that 

 Pieris whirls about all kinds of plants and projecting objects, that small Hymen- 

 optera such as Stelis and Prosopis fly about and land upon anything; finally, to 

 take for visits the momentary or accidental presence upon artificial flowers of 

 carnivorous insects or others that are not attracted by real flowers. 



"F. To employ the artificial flowers of commerce or those made by florists. Such 

 imitations may contain parts taken from natural flowers; they are nearly 

 always impregnated with starch; they are sometimes dyed with chlorophyll or 

 other plant colors ; the stamens and pistils are always represented by small balls 

 of paste more or less attractive to certain insects, faults whose importance I 

 do not wish to exaggerate, but which probably explain the cases noted of an 

 apparent search for pollen, of attempts to suck pollen, and of visits to the flowers 

 of ladies' hats." 



