38 



Tesas Agkicultural Experiment Sa'Aiioisr 



bisulphide upon the pupae. It was found that they are quite sus- 

 ceptible, but a long exposure to the fumes is necessary as the pupae do 

 not consume air very fast. 



From the experiments conducted with the moths, it was found that 

 they are very susceptible to the fumes of carbon bisulphide. With the 

 average dose the moths are overcome in from ten to fifteen minutes and. 

 are killed in from fifteen to twenty minutes after being confined. 



All fumigation should be allowed to continue for at least twelve 

 hours, for those larvae which are best protected by webs and refuse wiU 

 not be killed unless plenty of time is given for the gas to penetrate the 

 material. The liquid will evaporate in a few hours, but the resulting 

 gas will be effective for several hours. 



The following table has been prepared to show at a glance how much 

 liquid carbon bisulphide is required for effective fumigation of ten frame 

 supers and hive bodies containing infested material. 



Table'28.-;— Amount of carbon bisulphide to use in fumi- 

 gating ter frame supers for the waxworm. 



Table 29. — Amount of carbon bisulphide to use in fumi- 

 gatms ten frame hive bodies for the waxworm. 



For eight-frame supers and hive bodies, use eighty per cent, as much 

 bisulphide as is given in the foregoing table for the corresponding num- 

 ber of supers or bodies. 



Example : Suppose that the beekeeper has six ten-frame shallow ex- 

 tracting supers containing combs which he wishes to fumigate. All 

 are tiered up "as previously directed and an empty super is placed on 

 top. This makes seven supers in all. Reference to the preceding table 

 shows that this tier of seven supers contains 6.09 cubic feet of space 

 and that for the destruction of all of the waxworms in it one and one- 

 half ounces of the liquid bisulphide are required. 



