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Heart of the grain; it infinuates :: This creature, as if it forefaw itself first into the membrane, which that in its butterfly state it would separates the two lobes, where it have no organ left to penetrate the spins fome threads of its filk, it husk that inclofes it, has the prethen wounds the hufk with its caution to fashion with its teeth, teeth, but in fuch a manner, that in that part of it which is overwhen it has penetrated into the against the head of the chrysalis, farinaceous part of the grain, the a kind of trap door, large enough hulk collapses, and closes the aper- for the butterfly to issue out at, ture, fo as that it can scarce be per which continues tut till it has ceived, even by an inquisitive eye. quitted the fhuck of the chrysalis :

Many of them; however, perifh when this prudent meafure has been before they can get into the heart taken, the caterpillar spins a cod of the grain; either by fatigue or of filk, which exactly hills one of hunger, or by a contest among the lobes of the grain, the other themselves, which very frequently being filled with its excrements; occurs to decide the property of a the butterfly being disengaged from grain which happens to be attacked the chrysalis, forces his head thro by several at the same time. the cod, lifts up the trap door

One of these caterpillars is al- which had been made in the hulk, ways contented with one grain of and issues out, as it were alive, corn, and never leaves that which from a tomb, in order to propait has penetrated to attempt ano- gate its species. ther; but two of them are never Such is the circle of the life and found in the same grain ; one is transformations of this insect; but sufficient to consume it entirely; it is not easy to fix the precise time and withont any injury to the in which these transformations are hulk, it eats the contents of it fo effected, as they are retarded by clean, that nothing can be extract cold, and accelerated by heat, coned from what remains, even by fequently the number of generafoaking it in water.

tions which succeed each other It feems probable, in the highest within a year cannot be ascertained: degree, that this worm having de- In the most favourable season a gevoured all the farinaceous substance neration goes through all its funcof the grain, eats its own excre tions in about a month ; but that ments again and again. When it which passes the winter in the arrives at its full growth, which is grain lasts several months, the duabout a quarter of an inch long, ration of other generations may and about half the thickness of the be fixed at a medium between these grain it has consumed, it begins to two extremes. . Towards the end fpin its cod'; its body is without of May, or the beginning of June, hair, and entirely white, it has eggs, or the caterpillars in a very two protuberances, like horns, diminutive itate, are found upon upon its head, which are placed in the ears of the grain, as it is a direction towards the tail, near growing in the field; in July there which thete are two others which are butterflies which deposit a new have also the fame direction, and

pofterity upon the same ears, which gives birth to a second in the barn,

it has fix legs.

or in the granary, towards the end way out of the granaries, and at of August, if the cold of the ap- fun-set the swarms are seen spreadproaching winter is kept back, a ing themselves over the country, new brood is produced in Septem-' from the windows, and from under ber, and another still in November, the eves of the granaries; the if that month happens to be mild; Rights of the other seasons pass the according to this computation there day in reft, and at night become are five generations of these ver- very a&tive, flying here and there min in a year, but it is not neces. over the heaps of grain from which sary they should multiply so fast to, they issued, but none of these commit the most dreadful ravages. [warms are ever seen without doors. It is, indeed, fomewhat difficult The academifts to whom this to distinguish exactly all their ge- matter was referred, searched the nerations, because butterflies are fields by night in the spring, with continually seen issuing from heaps lanthorns in their hands, for the of grain, and each butterfly lives insects which were the objects of about a month ; but at certain their enquiry, and found them in times a prodigious number issue all great numbers coupled upon the at once, which is called a flight, ears of the grain which was yet and is always preceded by a coafi- green ; they communicated their derable degree of heat, generated discovery to the inhabitants of the in the heaps of grain, which will province, who then first undercause the thermometer to rise to itood the origin of the caterpillars, 25. 30. and even sometimes to which they found in June upon the 50 degrees, when the external air ear, and of the butterflies which will not raise it higher than 13 or they faw issue from it in July, 14. This heat may proceed either This discovery explained also from the great number of cater-” another phænomenon which might pillars ready for their transforma- greatly have embarrassed them, and tion, or from a general fermenta- Thewed the reason why those crops tion excited by an abundant tran- suffered ' most from this inseat, spiration, or even an evacuation of which were produced upon fields a certain liquor which generally contiguous to towns and villages; precedes the transformation of

the it having been observed that every caterpillar into its chrysalis. This 16th, 20th, 30th, or 4th grain heat very confiderably favours the of a crop was attacked, according progress of the caterpillar through to the granary's dillance from any the several stages of its existence; habitation in which there but when a flight is not at hand, chamber with grain in it in the the heat of the grain is very little spring. greater than that of the external air. The deputies of the academy

There are generally three flights broke up a piece of ground in in a year; one the latter end of 1760, in the forest of Braconne, May or the beginning of June, a having no granary within a great fecond in August, and a third in distance, and lowed it with grain fome of the subsequent months. which had been brought from a The butterflies produced in the province which the ivfect had not spring flight, always niake their yet infested; 'buc notwithstanding

was a corn

there

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these precautions, in the harvest till the next summer if they were of 1761. they found every 8oth not more than three inches below grain affected, though this crop the surface, and the earth was not was less damaged than any other close, compact, and a little hard, in the province. It appears from in which cases they would infallithis fad, that the corn-butterfly is bly perish, capable of a long flight.

It appeared also that they would The following calculation will live and multiply in oats, as well few the astonishing multiplication as in wheat, barley, and rye, in of these insects, and consequently which they were most commonly the ravages which they make where found, and that the eggs were de. they have already established them- pofited between the two grains selves, and with which all the that grow on one pedicle, which neighbouring provinces are threat." is fastened to the them that forms ened.

part of the ear, and that they Every female produces from 60 would also be produced and thrive to 90 eggs, of which 75 is the in Spanish wheat or maize, if medium; but let us suppose the maize was in a state to receive the number to be no more than 70. eggs when the butterflies lay, Let us suppose also, that of these which happily is not the case. 70 eggs, one half only produce The reader will now think it females, which makes the number happy, that a method has at last 35. This multiplied by 70, the been discovered, by which these number of eggs laid by each, destroyers of the staff of life may gives for the second brood from a be extirpated, and the grain presingle insect, 2450 : the half 'of served from harvest to feed-time. this number supposed to be females [For this method fee our article of is 1225, which multiplied by 70, Projects for this year.] gives 85,750 for the third brood. Half of this number 42,875, multiplied by 70, gives for the fourth The history of the fly called a Bort, brood 3,00 1,250°; half of this from Mr. De Reaumur. 1,500,625, multiplied by 70, gives 105,043,759 for the fifth brood : so that, supposing five broods in a

AMONGST the animals that are

useful to mankind, the horse year, each female butterfly of this is certainly entitled to the first species that exists in May, pro- rank; and yet this animal, confia duces, before the May following, derable as it is, and contrived by no less than one hundred and five its figure and beautiful proportion millions, forty-three thousand, to afford us pleasure, was not given feven hundred and fifty individuals to mankind alone ;

there is a of the same kind.

species of Ay, whose right in this It appeared also in the course of

creature may be looked upon as the experiments made upon these still better founded than our own. insects, that the caterpillars which If the horse be useful to us, he is were surprised by the winter be, absolutely neceffary to this fy -- the fore they had passed their chrysalis fame Being that formed the horte; 4ate, would survive in the ground formed allo this fiy, which de

penda

pends wholly on the horse for its yet M. Vallisnieri fays, that Dr. preservation and continuance. The Gaspari had attained this very undies we are speaking of, like those common sight. The doctor (he of all other species, receive their tells.us)was one day looking at first life and growth in the form of his mares in the field, and from worms, but these are worms being very quiet he observed, that that can be produced and nourish- on a sudden they became very refted only in the intestines of a horse. less, and ran about in great agita

. It is there alone they can enjoy tion, prancing, plunging, and the proper temperature of heat, and kickingwith violent motions of receive the nourishment necessary their tails. He concluded, that for them.

these extraordinary effects were Besides the long, and sometimes produced by some fly buzzing, avery long worms which have been bout them, and endeavouring to observed in the bodies of horses, settle upon the anus of one of there have been alfo fhort ones. them; but the fly not being able

[By these are to be understood to succeed, he observed it to go what we call Botts. ]

off with less noise than before, toAll authors, both ancient and wards a mare that was feeding at modern, who have treated of the a distance from the reft; and now diseases of horses, have taken no the fly taking a more effe&tual metice of these worms-but M. Vala thod to obtain its design, passed lifnieri is, I believe, the first who under the tail of the mare, and fo has traced them to the last stage of made its way to the anus. their transformation, and has seen Here at first it occasioned only them change into a hairy kind of an itching, by which the intestine fly like the drone.

was protruded with an increased The Aies from which these botts aperture of the anus ; the Ay takare produced inhabit the country, ing the advantage of this pene. and do not come near houses, at trated further, and secured itself least not near those of great towns; in the fold of the intestine;-this and therefore horses are never effected, it was in a situation proliable to have these worms (i. e. per for laying its eggs. Soon after botts) in their bodies ; if they this the mare became very violent

, have have been kept in the house, running about, prancing, and kickespecially in a town, during the ing, and throwing herself on the summer and autumn.

ground; in thort was not quiet, It is in the former of these sea nor returned to feeding, till after fons, and perhaps too in the be a quarter of an hour. ginning of the latter, that the fe

The fly then we males of these dies apply them- means of depositing its eggs, op seives to the anus of horses, and perhaps its worms (i.e. botts) in endeavour to gain admittance, in the fundament of the horse, which, order there to deposit their eggs, once effected, it has done all that or perhaps their worms.

is necessary for them. The precise instant of their en If these bott worms are not trance will scarce admit of an eye- hatched when first deposited in witness, bụt by the meerest chance; the horse, but are then only egy

fee can find

as

it will not be long before it hapa There is a difference in colour pens, from the nutritive heat they observable between those that are there receive.

taken by force from the intestine Thefe bott worms, foon 'make of the horse, and thofe which their way into the intestines of the come away of their own accord; horse; they occupy such parts of fome are greenish, fome yellowish, this region,

are to them most and others nearly brown; thefe convenient; and fometimes (as we laft are nearest to, and the greenish fhall fee presently) they penetrate

ones the fartheft from the time of even to the stomach : all the ha their transformation. zard they appear to be exposed to, If M. Vallisnieri and myself is that of being carried away from have rightly observed the position the places they have fixed on by of their claws, fome of them differ the excrement, which may seem from each other in this refpe&t; likely to drive all before it. But but are perfectly fimilar in every nature has provided for all things, other particular, and which change and when we shall have further into flies fo nearly alike, that I am described these bott worms, it convinced, they are of the fame will be seen that they are able' tó kind and origin., maintain their fituation, and to However this be, the bott remain in the body of the horse as worms, which are the subject of long as they please.

our present pursuit, have two unThere is a time when these equal claws; and since I have been bott worms" are of themselves acquainted with the nature and use desirous to leave this their habita of them, I have had no difficulty tion, it being no longer conve to conceive, how they may ftill nient to them after the purposes of remain in the intestines of the their growth are answered. Their horse, in opposition to all efforts transformation to a fly must be of the excrement to force them performed out of the horse's body, out-one of them, that I was and accordingly, when the time of handling and examining, faftened their transformation draws near, upon my finger in such a manner, they approšėh towards the anus of that I found great difficulty to the horse, and then leave him of disengage myself. There claws their own accord, or with the ex are a fort of anchor, differently crement, with which they then disposed from those of common fuffer themselves to be carried anchors, but contrived to produce along.

the same effect, The figure of these 'bott worms Besides these two claws, nature affords at first fight nothing re- : "has given to each of these bott markable, but they appear like worms a very great number of trimany other worms of the first class, angular spines or bristles, very to which they belong, that change sufficient to arm them againft the into flies with two wings, and like coats of the intestines, and to rethe greatest part of the worms of fist the force employed to drive that class, they are provided with them towards the anus, provided a fort of scaly claws, with which the head be directed towards the they draw themselves forward. ftomach of the horse,

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