REPORT OF THE ENTOMOLOGIST. 



349 



this also should be thought too expensive, some simple contrivance can 

 easily be arranged by means of which the ordinary crib can be rendered 

 temporarily tight enough for the purpose. A cloth covering, painted 

 or varnished, so as to render it water-proof and as tight as possible, 

 could be cheaply made so as to cover the entire crib from the top of the 

 roof to the ground. After every crack has been closed as tightly as 

 possible, an open vessel containing bisulphide of carbon should be 

 placed on the corn. This substance is extremely volatile, and at the 

 same time in the form of a vapor it is heavier than air and would rap- 

 idly permeate the mass of grain. The greatest of care must be taken 

 with the bisulphide, as it is extremely inflammable, and no exposed 

 flame should be brought into its vicinity. In the summer of 1876, at 

 the Department, we had experiments made with this sabstance on this 

 and other grain weevils, employing for the purpose a large zinc box. 

 The experiments were satisfactory on this small scale, and the idea of 

 using it on a larger scale was first suggested by us later in the Fann- 

 ers 1 Review for March, 1879, in an article on the Eice weevil. 



Mr. Edward Kuffin's remarks on the simpler prophylactic plans are so 

 sensible that we quote them in full : 



u l. Corn maybe kept for years nearly exempt from the attacks of 

 the weevil by being housed in the shuck, or husk. I have known it to 

 be thus kept through the third year, and much more free from injury 

 than shucked corn is in August, and even the July succeeding the 

 gathering. But this mode requires much more house-room and much 

 additional labor, if adopted for the whole crop or for that portion de- 

 signed for sale; still, all required for bread at home, after the beginning 

 of summer, may be well and ought to be kept in the shuck. The reason 

 of exemption from the weevil is obvious. The few larvae which may be 

 in the corn when housed in autumn, perish because they are not able 

 to escape from the compact bulk; and the same compactness prevents 

 the access of laying-moths approaching from other places. The grains 

 exposed by the opening of the shuck, and those only of ears at the out- 

 side of the bulk, are all that can be reached or sutler from the weevils 

 at all. 



"2. If, instead of keeping the corn in the ear and shucked, as usual, 

 until wanted for food or market, it were shelled in May, or before the 

 coming out of the first summer broods of weevils, and kept in bins or 

 in bulk, there would be very little damage from all the succeeding geiv 

 erations. The first few moths would perish by confinement, except those 

 produced in grains then on the surface of the bulk; and none others 

 could deposit otherwise than* on the surface of the grains. It is obvi- 

 ous that every change of the surface exposes to such injury a new layer 

 of grain before untouched, and, if left undisturbed, the surface grains 

 will serve to shield all below them. When the corn is about to be sold, 

 the weevil-eaten surface of the bulk may mostly be separated by strong 

 fanning or a previous raking off' of all the surface corn, which may be 

 reserved for stock-feeding. 



u 3. Wheat, as soon as reaped, and perhaps sooner, is supplied from 

 the granaries with a greater or less number of parent weevils to lay 

 the earliest brood, and if it remains in the straw until September, and 

 when threshed is left in small bulk, or often stirred, nearly all the grains 

 may be weevil-eaten; but if wheat be threshed and well fanned early in 

 July, in this region, there will be no weevils worthy of notice. The eggs 

 previously laid probably do not exist on the grains, but on the chaff* or 

 shuck in which they are inclosed, and, in hatching, the maggots must 

 perish for want of food. As in the case with corn, the bulk of clean 



