Insect ITfsftors. 217 



to a floral diet, have led to more adaptive modi- 

 fications in these flowers than the Orthoptera 

 and Neuroptera, the Hemiptera, the Coleoptera, 

 and the Diptera and Thysanoptera combined. 

 To them we owe the most varied, most numer- 

 ous, and most specialized forms, the flowers 

 adapted to the Apidce probably surpassing all 

 others together in color-variety. 



The Hemiptera, to which belong the bugs, 

 stand higher than the Orthoptera and Neurop- 

 tera, to which belong the cockroaches and 

 dragon-flies, several species being fitted by their 

 small size to creep into and suck honey from 

 very various flowers. The Coleoptera, to which 

 belong the beetles, are of much greater impor- 

 tance as fertilizers, for many species in widely 

 different families feed at times on flowers, and a 

 still greater number confine themselves to such 

 food exclusively. On the other hand, the vora- 

 cious beetle does much harm to numerous flow- 

 ers by nibbling their reproductive organs. 



The Diptera, to which belong the flies and 

 gnats, stand on a still higher plane than the 

 Coleoptera in the matter of adaptation to a 

 floral diet, and are of far more importance for 

 fertilization, the majority of Diptera resorting to 

 flowers. In the habits of the Empidce of the 

 general order Diptera, Miiller clearly sees the 

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