15 



of soda or Paris green. As a rule, however, they are dug out by 

 hand. The natives are fond of these crickets for eating pur- 

 poses, and take kindly to the work of capturing them. 



GRASSHOPPERS. Several species of grasshoppers attack 

 the tobacco in the seed beds and in the field, mostly in the 

 earlier part of the season. When serious, they can be des- 

 troyed by spraying, as for caterpillars, with an arsenical pre- 

 paration. Transplants can be dipped in poison as far as the 

 roots as a protective measure. 



THE CIGARETTE BEETLE (Lasioderma serricorne). Stored 

 tobacco in Ehodesia is very much subject to attack by this cos- 

 mopolitan insect. The whole life of the beetle is passed in the 

 tobacco, and, under favourable conditions, the rate of increase 

 is very rapid. Bales of tobacco may be ruined if left to them- 

 selves for a season or two. Cigarettes and cigars are also 

 attacked. The different stages of the insect are shewn in the 

 plate very much enlarged. This pest, of course, concerns the 

 manufacturer rather than the grower, as the latter rarely 

 wishes to hold his stock longer than necessary. The beetle can 

 be destroyed by fumigation for 24 hours with carbon bi- 

 sulphide, at the rate of 1 Ib. to 1,000 cubic feet of space, but 

 bales need to be opened up to enable the gas to penetrate. This 

 gas is poisonous, and, when mixed in certain proportions with 

 air, highly explosive, so its use calls for caution. 



TRIBOLEUM CONFUSUM. This is usually a pest of grain, 

 meal and other stored products, and it occurs over the greater 

 part of the inhabited world. Ehodesia is apparently the only 

 country where this pest has been recorded as attacking tobacco. 

 It seems likely that the attack is generally dependent upon the 

 proximity of infested grain or meal to the tobacco. The insect 

 has not been found to breed in tobacco, but to attack it freely 

 enough in the adult or beetle stage. Eemedial measures that 

 apply to the cigarette beetle will be effective in the case of 

 triboleum. 



TOBACCO AS AN INSECTICIDE. Tobacco has a considerable 

 value as an insecticide. It is used as a fumigant for green- 

 houses, in the form of snuff for dusting on the plants and as an 

 infusion. It is effective against plant lice, thrip and other soft- 



