102 
Observations on the various Insects 
that a heat of 60° or 70° (167° or 190° Fahr.) is necessary to kill 
the weevils in the stove; but this excessive heat, which has the ad- 
vantasre of destroying the eggs and larvae inclosed in the grain, is 
capable of drying the corn too much, even of burning it, and yet 
does not preserve it from the insects secreted in the granary, 
which will come out and attack it if there be no other for them." 
In a short communication to the Entomological Transactions, 
some valuable data upon this point are furnished by Mr. Mills, 
who was in Madeira from January to August, 1835. In that 
island he thinks the eggs are first deposited whilst the maize is in 
flower, and he ascertained that he could hatch the eggs at 110° 
of Fahr., whilst from 130° to 140° of heat killed them. He 
adds, " A gentleman of the name of Wilkinson, in Madeira, has 
now established a heated room with hot-water pipes, in which he 
receives as many as 800 bags of wheat at a time ; these become 
heated through at about 135°, and the wheat, when resifted, is 
perfectly cleansed from these noxious insects, and makes quite as 
good bread as before. I also tried some of it in the ground that 
had been subjected to this heat, and it came up."* 
Olivier then recommends a ventilator to introduce cold air 
which has already been discussed in the remedies proposed for 
"the Grain-moth," as well as the forming of little heaps of corn 
in the spring to act as decoys. He says that when the weevils 
have taken possession of them, boiling-water should be poured 
on the heap, at the same time turning it over with a shovel, in 
order that the heat may penetrate everywhere : it ought after- 
wards to be spread to dry, and then sifted to free it from the dead 
weevils. This should be done at the commencement of spring, 
before the eggs are deposited, by which precaution a fresh 
generation is stopped. f The introduction of cold air is. 1 expect, 
to be recommended for various reasons : at Lynn in Norfolk I 
have heard it is the practice, and the readiest way of getting rid 
of the corn-weevils, to expose an empty granary to two or three 
nights' frost by setting all the windows open. 
In a French work we are told J it is an excellent plan " to lay 
fleeces of wool, which have not been scoured, on the grain; the 
oilv matter attracts the insects amongst the wool, where they soon 
die, from what cause is not exactly known. M. B. C. Payran- 
deau related to the Philomatic Society of Paris, that his father 
had made the discovery in 1811, and had since practised it on a 
large scale." 
After all that has been said, 1 shall only revert to the necessity 
* Observations upon the Corn-weevils, by William Mills, Esq., F.L.S. ; 
Tians. Ent. Soc, vol, i. p. 241. 
•!• Ency. Method., vol. v. p. 444. 
;|; Bulletin des Sciences Agric, July, 182G, p. 24. 
