90 



Several species are injurious to the roots of cereal crops, corn 

 potatoes. 



and 



Life History. In general the adult beetles emerge from their pu- 

 pal cells in the ground in May, and lay their eggs in grass land on, or 

 close to, the crown of the roots. The eggs hatch in a \veek or so and the 

 grubs feed on tender roots. The development of the grub is slow for it 

 does not mature until July or August of the following year when it 

 changes to a pupa in an earthen cell. Tn another month the pupa trans- 

 forms into a beetle, but it does not emerge until the following May. 'iue 

 life-history of most of the species is not thoroughly known but that 

 given above is believed to be fairly accurate though there are exceptions. 



Melanotus cribulosus : The Corn Wireworm ; a. adult beetle ; b. wireworm or larva ; c. last segment of larva. 



Kinds of Wireworm s. The species most common and best 

 known are the foUow^ing: 



(i) Wheat Wireworm (Agriotes mancus), cylindrical, pale 

 brownish yellow, with two black pits on the last segment which ta- 

 pers gradually to a brown point. The pupa is pure white, and soft, and 

 lasts about 3 w^eeks. The adult beetle is dark bro-wn, with coarsely and 

 densely punctate convex thorax; front or clypeus convex. 



