The Indian Wheat and Rice Weevil. 15 



APPENDIX. 



' English grain bein^ affected is due always to carelessness or heedlessness in shooting 

 it in old dirty, uncared-for granaries or mills, which themselves are sure to harbour the 

 little beetles, or by laying it in close proximity to some affected foreign corn. With 

 foreign wheat, weevils are a necessity, as it is either affected on shipment or speedily 

 becomes so from the dirty, unswept, and uncleaned granaries into which the corn finds its 

 way. The little, pests would certainly be got rid of by shippers to a great extent if they 

 would only try. The improved service and quickened passages have lessened weevil loss 

 in corn to a remarkable extent within the last few years.' 



* The wheats which are now affected to any very serious extent are the Indian, and I 

 have often seen samples of the excessively dry Calcutta and South- Eastern Asian wheat 

 in which it was almost impossible to find a perfect corn, the valuable starch of the kernel 

 being consumed by the destructive little weevils.' 



' Weevily wheat is invariably dressed after landing, and a large percentage of tlie little 

 beetles are thus screened or blown out, but of course manv of the perfect insects resident 

 in the corn, and all in the larva or pupa state, escape, the kernel not yet being light 

 enough to be separated. When the cargo is very badl}' affected, when the whole bulk 

 seems alive, as 1 have myself seen it on very hot summer days, it is a common practice 

 for merchants to spout it, )'.e., to shoot the gram down a spouted trough in which, at the 

 angle, is a wire sieve with meshes large enough to let the weevils pass through, but not the 

 corn, which runs into the granary, or into sacks as the case may be. By such means the 

 quantity of weevils and dust sifred out is enormous, and this appliance is generally so 

 situated at the wharves that the beetles are deposited near the edge] of the wharf or even 

 in the river bed, and if not naturally washed away at high tide, are swept into the water, 

 their destruction being thus easily accomplished. The great heat generated in a bulk of 

 weevily corn is caused by the dust arising from the borings and frass of the insects. 

 The weevils themselves are generally to be found inside the granaried heap or caro-o of 

 corn, unless the weather is very hot ; they then are specially lively on the outside.' 



' Although these granary weevils are the most destructive enemy to stored corn, they 

 leave sound what they do not actually attack. This is not so with that other o-reat 

 enemy, the wolf-moth {Tinea granella, L.) which spoils more than it eats, by spinnino- the 

 grains together with its dirty silken web, and thus becomes a more troublesome pest, per- 

 haps though less destructive than the Calendra. In all weevily corn, the snouted uni- 

 colorous SitophUus granariiis, and the Sitophilns oryzm which has two red spots on each 

 wing case, will be conspicuous as the most abundant and most destructive insects. A.s far 

 as my own experience goes SitophUus oryzce is by far the commoner of the two.' 



' The increase of these Calandridsc and their allies is naturally limited by internal hyme- 

 nopterous parasitism. I have met with two (probably three) species of Chalcidida^ and 

 Curtis knew another. About a dozen Cerocephala formiciformis, Wcstwood, or a very 

 closely allied species, were bred.' 



' To return to the actual economy of the SitophUus, the two species are so closely allied 

 that, practically, they may be considered as one. It has been usuallf supposed that the 

 parent weevil bores with its rostrum into the grain previous to depositing its eo-g in the 

 hole made. I do not believe this is the case, for a very fine puncture only, such as 

 would be made by a very fine needle, is to be seen on the borders of the germen in those 

 grains which contain the larva. The egg is, therefore, laid, I think, just on the surface 

 as Olivier says, or under the outer skin of the gerraen, and the young larva eats its way in. 

 One egg only is deposited in a grain, the flour of which just serves to bring the larva to 

 maturity. It turns to pupa in the grain, so that, unless very minutely examined, affected 

 grains are not apparent until the emergence of the imago, except by their weight. The 

 imago partially feigns death when touched, and on a tolerably smooth surface, such as a 



