24 



INJURIOUS INSECTS OF 1904. 



larvae. Some mills, in order to avoid infection, will not take back 

 old sacks. If a milling company must do this such material should 

 be thoroughly treated before beiug alloivcd in the mill. A fmnigation 

 house, or room, might be constructed, where sacks or machinery 

 could be fumigated. If sacks have been in transit for more than 

 nine days, and during that time free from all sources of contagion, 



Fig. ] I.— Silk felt spun by larva; in crawling across bolting cloth on top of breeding jar; 

 showing also larvs, pupa, cocoons, and moths somewhat reduced. Original. 



all eggs which may have been originally in the package have 

 hatched, hence, one need not seek for a treatment which will kill 

 them (the eggs), but only for such as will kill the worms which 

 have hatched from the eggs. Carbon bisulphide is the best and 

 safest fumigating material at our disposal, and could be well used 



