ENEMIES OF THE SUGAR BEET. 281 



nineteenth family (Scenopinidse), the latter being the 

 second general division (Brachocera) of the Diptera 

 insects.^ 



Fig. 73. 



Diptera. 



The Phytomyzide deposits its eggs on the leaves 

 of the beet, and the resulting larvae devour and pene- 

 trate the root by the lower portion of the stem, thus 

 causing much harm. 



The second insect of this group is the Hylemyie 

 coarcata belonging to the seventh species of the third 

 class of Diptera.^ Yery little is known in regard to 

 this insect. 



We conclude from all that has been said, regarding 

 the insects already named that the best plan of destruc- 

 tion is to compress the soil with a heavy roller, thus 

 causing these enemies to perish. Such is what man 

 can do, but nature has furnished moles and birds that 

 destroy without trouble the greater number of them. 



If the farmers of all countries would only understand 



' The above classification is the one adopted by Westwood. 

 ' For those who wish information concerning the Diptera, we advise them to 

 readMaquart, "Diptcre exotique." 

 19 



