VIII, D, 1 



Jones: The Cigarette Beetle 



23 



for 1,300 pesos, or a common wooden compartment can be built 

 in which the effective temperature could be secured. This latter 

 could be erected at a cost not to exceed 100 pesos. The drum 

 illustrated by fig. 1, Plate IV, is preferable, as in the two last 

 mentioned, the tobacco must be removed by hand, and since there 

 is no carriage the tobacco comes in direct contact with the sides 

 of the drum or compartment and there is greater danger of 

 getting it too wet by condensation. 



After the tobacco has been subjected to the steam for twenty 

 minutes at about 4 atmospheres, the exhaust is opened on the 

 outside of the building. The door is then opened, the car pulled 

 out on the track, and the tobacco shaken out. After steaming, 

 at least one day is required to dry the tobacco before it can 

 be made into cigars, and a small screened apartment for this 

 purpose is necessary. After completion, the cigars should be 

 guarded against reinfestation as in the cases of fumigation. 



After steaming leaf tobacco in the drum for a period of twenty 

 minutes at the above temperature, all insects found were dead. 

 Experiments were tried with the cigarette beetle in all its stages, 

 submitting them to temperatures from 60° to 90° C, for periods 

 from ten to twenty minutes, and in each test all the insects 

 were killed. The minimum effective temperature was not de- 

 termined. However, this is not necessary as the temperature 

 in drums while subjected to steam never falls below the killing 

 temperature. Tobacco steamed as described above, placed in a 

 screened room to dry, then made into cigars and kept under 

 conditions to prevent reinfestation, proved good at the end of 

 eight months. 



Table XIII gives the results of the various temperature 

 experiments. 



Table XIII. — Effects of different temperatures on different stages of the 



cigarette beetle. 



Temper- 

 ature. 



Time sub- 

 jected. 



Stage of insects. 



Remarks. 



Eggs. 



Larvae. 



Pupse. 



Adults. 



°C. 

 90 

 85 

 80 

 75 

 70 

 65 



60 



Minutes. 



20 

 10 to 35 



20 

 10 to 35 



20 



20 



20 



20 

 60 

 20 

 60 







20 

 20 



All the adults were dead when re- 

 moved. The larvffi, pupse, and eggs 

 were kept in dishes to determine if 

 dead or not. All larvae and pupae 

 turned black after two days. Eggs 

 were kept two weeks and examined 

 under the microscope. All were 

 dried; none hatched. 



Check eggs in these experiments all 

 hatched. 



70 



15 



50 







40 









20 

 20 









20 



20 



20 



