174 



only one l.u-va pntprs each grain, but when com is attadccd. two or three 

 larvte may be found in a single Icernel. After couiiileting its growth the 

 caterpillar spins a thin, silken cocoon, and within this changes to a brownish 

 pupa : in a few days later the moth emerges. The perfect insect resembles 

 somewhat a clothes moth. The wings expand about half an inch, are of a 

 satiny-cream colour and bear a few dark spots on the fore wings, which are 

 narrow, pointed and fringed. The hind wings are darker and have much 

 wider fringes. 



Remedies. — When stored grain is found to lie infested by une of the 

 above three Insects, or. in f.-u-t. by any insects which are known to work in 

 dry cereals. It is a simple matter to destroy them. After repeated experi- 

 ments, it has been found that the use of bisulphide of carbon will kill all the 

 insects without any injury to the grain as to its wholesomeness for food, or 

 as to its germinating quality for seed. Bisulphide of carbon is a colourless 

 liquid with a very objectionable odour, which vaporises quickly at the 

 ordinary temperature of the atmosiihere. A convenient method for treating 

 small quantities of infested grain, is to fill an ordinary coal oil barrel, which 

 will hold about five bushels of grain, and the quantity of bisulphide to use 

 is one ounce to every htmdred pounds of seed. The bisulphide may be 

 poured right on to the grain or placed in a shallow receptacle, but care must 

 be taken to close up the top of the barrel tightly. This is best done with a 

 cap made specially for the purpose, but may also be done with fine sacks 

 laid smoothly ou the top, over which boards are laid, with a considerable 

 weight on them to hold the covering down closely. When grain in bins is 

 being fumigated with bisulphide of carbon, these should be made as nearly 

 air-tight as possible. This may be done by pasting sheets of paper over the 

 outside, or by covering them with blankets or canvas. In tight bins the 

 amount of bisulphide to use is a pound to a pound and a half to the ton of 

 grain. Some entomologists claim that one pound of bisulphide to every 100 

 bushels of grain is sufficient to destroy all insects, even in open bins. 

 Infested grain should be sulijected to the fumes of bisulphide of carbon for 

 at least 4.S hours, but as the vapour is very intlanmiable, no light of any 

 kind must be brought near and no smoking must be allowed near the building 

 when this chemical is being used. 



In Queensland it has been found that salt (1 quart ilissolved in 2 gallons 

 of water) will prevent weevils from attacking grain which has been sprinkled 

 with this solution. — The Cunudiaii Eiitoiiioloijist. 



