200 



AN ECONOMIC ENTOMOLOGY. 



poisons act too slowly, as two or three days suffice to ruin a vine- 

 yard. Lest this seem strange, I will state that I have seen on 

 hundreds of acres of vineyard every vine bearing multitudes, and 

 every bunch of blossoms from two to ten, or even more beetles. 

 I have counted over twenty on a single apple, and a full-blown 

 rose may bear as many as thirty or even more. We are reduced 



Fig. 189. 



Larva, a, and pupa,/", of rose-chafer ; b to e, g, A, structural details. 



to actually collecting the specimens from the vines by means of 

 funnel or umbrella-shaped collectors, adapted to the method of 

 cultivation in use. They drop readily when the vines are jarred, 

 and the collector should be so made as to roll them to the centre 

 and into an attached pail containing kerosene. This must be 

 done not only daily, but continuously for several days until the 

 flight is over or the grapes have set, for well-set grapes are 

 rarely eaten. Fortunately, a period of abnormal increase seems 

 to be followed by a period of decrease, though the lengths of the 

 periods have not been ascertained. The larvae feed in light land 

 on the roots of various plants, but principally on grass. They 

 pupate in spring, shortly before changing to the adult condition, 

 and by ploughing infested sod at this time a large proportion can 

 be destroyed. When only moderate numbers occur, Hme often 

 serves to protect the plants, or, better, the Bordeaux mixture, 

 which is distasteful to them. 



The "May-beetles," or "June-bugs," sometimes termed 

 " cockchafers," are much larger, and mostly members of the genus 



