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the day into granaries infected with them. While the day lasted, they perceived a multitude of butterflies, which stirred a little upon the heaps but did not quit them. When they returned into the same granaries a little after sun-set, they saw those butterflies rise and fly to the walls, where they settled for a while, after which they took their flight in vast numbers through the windows. As these little insects fly very swiftly, and rise to such a height that the eye cannot follow them long, especially when the dusk of evening comes on, Messrs. Duhamel and Tillet were obliged to try several methods before they could be certain what became of them. The caterpillars found in the standing ears made them conclude that the butterflies, when out of the granary, flew directly into the green grain and laid their eggs upon it while yet tender; but none of the country people of whom they enquired had ever observed them in the fields, or could give any satisfactory account of them. They searched all the neighbouring fields, and beat even the surrounding hedges at all hours of the day, to no purpose-not a butterfly could they find, excepting a few dead and dried ones entangled in spider-webs. This very circumstance led them to the discovery they were in quest of; for rightly reflecting that these insects, which neither they nor any other persons had been able to find in the fields in the day-time, must certainly be of the phalence or nocturnal kind, they without farther delay set out with a candle and lanthorn, repaired to one of the fields they had visited in the afternoon, and soon descried a great number of the very butterflies they were seeking for upon the beards of the ears of wheat. They returned to the same spot early the next morning, and could not then find a single one. It was proved by the following experiment,

experiment, that it is possible the caterpillars may live under ground, pass the winter there inclosed in the grain with which they are sown, and even undergo their several metamorphoses in the earth, so as to arise from thence in the form of butterflies in the spring. A wooden box was divided into three partitions, and filled with common mould taken out of a kitchen-garden, Wheat, known to be infected, was planted an inch deep in one of these partitions, two inches deep in another, and three inches in the third. All of them were then covered with a glass frame, and butterflies soon appeared in each of the divisions, but they were far the most numerous in that where they had been buried but an inch deep. In another trial a number of infected grains were covered with a still stiffer earth, wetted and pressed down, and not any butterflies appeared there. From hence, Messrs. Duhamel and Tillet concluded that though some of these insects can and certainly do come out of the ploughed ground which has been sowed with infected grain, their number is comparatively small, and that mills and granaries are the great source of their increase; for the grain which contains a young cater pillar, will grow if its germ has not been damaged, and as its mealy substance is consumed by the plant, the caterpillar must die for want of food; besides, as is proved by the experiment above mentioned, the butter. flies cannot pierce through a close and hardened earth, which generally is the case of ploughed land that has been exposed to the winter rains. It is not agreed whether these insects prefer wheat, barley, or rye. The observations made by Messrs. Duhamel and Tillet seem to prove that they attack indifferently whichever lies. most convenient for them; and that they do not spare

Indian corn when stripped from its stalk, and laid up in a granary where they can come at the soft inside part of grain. Even oats, when mixed with wheat, barley, and rye, in a glass vessel into which some of the butterflies were put, were damaged by caterpillars as much as any of the other grain, though it is certain that they do but little mischief to oats in the granary.

To preserve the grain from farther injury after it is reaped, it should be threshed out as soon as possible, and such part of it as it is wished to preserve either for seed or grinding, should be dried in an oven or kiln, in which the heat should be strong enough to kill the caterpillars without destroying the vegetative principle. This will be effected by 124 degrees of heat of Fahrenheit's thermometer. Or the seed-grain may be better prepared by being soaked in a strong ley of wood-ashes and quick-lime heated to such a degree that the finger can just bear it. Let the grain, contained in a basket, be stirred in this ley, and the grains skimmed off that float on the surface. When it has been thus soaked for about two minutes, the basket which contains it should then be lifted up and suspended by two poles till the ley is drained off. The grain should then be spread very thin on a floor to dry, while a second basketful is prepared in the same manner. When thus steeped and well dried it will keep a year, and continue fit for sowing.

In France mills and granaries, where large quantities of grain were deposited, seem to have been considered as the chief sources of the evil. But in this country it cannot be the case, at least not to so great an extent. No large quantities remain on hand when the warm season approaches, and kiln-drying might destroy any caterpillars which might then exist. It appears that the

severity

severity of a hard winter cannot be depended on for this purpose, but that a sufficient number may survive, even in the grain sown, to cause considerable mischief. The roller may, however, be of service to prevent the fly from making its way out of the ground. The principal danger seems to exist in the Spring barley, which having been kept under cover during winter, and afterwards sown in fresh-ploughed, and consequently light soil, will, if at all affected, be sufficient to spread the evil far and wide. To this cause the writer chiefly attributes the damage last season to a crop of wheat, the seed of which had been brought from a distance, and was perfectly free from the fly, which the barley was not, and was sown in the same field. If attention be paid in the ensuing spring to the kiln-drying of the grain that remains on hand, to the rolling of that which is coming up, and the pickling of the seed-barley, we may hope to put a stop to this distressing calamity, or at least to prevent its spread; but let it be remembered, that the remedy in order to be effectual, must be universal Lower Dublin, Feb. 1805.

Account of the Produce of Milk and Butter from one Cow.
By the Earl of CHICHESTER.

From the COMMUNICATIONS to the BOARD OF
AGRICULTURE.

THE following is the (second year's *) account of the produce of milk and Butter from a cow, the property of William Cramp, of Lewes, in the county of Sussex, for this season, commencing the 19th day of April 1806 (that * For an account of the first year's produce see our tenth volume of the present, scries, page 37.

VOL. XIII.-SECOND SERIES.

Ddd

being

of February 1807, a space of time of forty-five weeks. being the day on which she calved) up to the 27th day

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BUTTER.

From the 19th of April to the 2d of
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From the 3d May to the 23d May
From the 24th May to the 6th June..
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From the 7th June to the 3d October.... 16
From the 24th May to the 6th June ..... 14

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