THEIR RELATION TO PLANTS 



37 



Diptera or flies are often intimately associated 

 with flowers, and many of these are hairy, some even 

 with spurred or compound hair; but none with modi- 

 fications that adapt them especially or peculiarly as 

 pollenizers. We have one family, the BomhyliidcB or 

 bee-flies, resembling bumble-bees somewhat in appear- 

 ance and quite as hairy, many of which also have a 

 long tongue rivalling some of the Lcpidoptera. But 

 their habits are quite different. One 

 never sees them buried in a flower 

 or rolling about among the blos- 

 soms, pollen-covered. On the con- 

 trary they usually hover daintily over 

 bare, sandy areas or, if over flowers, 

 then very delicately and resting 

 lightly when at all. That they are 

 of some use to the plants is prob- 

 able; but they have no important 

 function. And the same is true of 

 the SyrphidcB that are found so 

 often resting on or about blooms: 



the majority of these are bare, or have only a thin soft 

 vestiture and slender hairless legs to which pollen 

 could not adhere if it would. 



An exception to this general statement is found in 

 the chrysanthemum or "drone fly," a burly bustling 

 species that becomes conspicuous late in the season 

 and resembles in size, color and general appearance a 

 honey bee, for which indeed it is often mistaken. A 

 little experience, however, shows that it has no sting, 

 and therefore the term " drone fly " is not so 

 inappropriate. 



Growers of chrysanthemums believe this fly of 

 great importance in the pollination of that plant and 

 they may be correct; but on other plants or flowers 



Fig. II.— Chrysanthe- 

 mum fly; Eristalis tenax. 



