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tance be considered as the effect of emerged into day, we thought our. enthusiasm ; a whole day may be spent selves newly awaked out of a dream here without having time to view eve which we were sorry had ended. ry thing that is worthy of being seen. There may be in the bowels of the

After having spent in these caverns earth other grottoes as beautiful as twelve hours and a half, we left them this ; but my persuasion, that none of without having suffered any disalter them can excell it, is the only motive except extreme fatigue. The air is that has prompted me to publish this moitt without being noxious; it is description, for the exactness and ay, even friendly to weak lungs. When thenticity of which I shall be answer. we left this place of enchantment, and able.

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Account of the Infects called Aphides, and Remarks on the Natural History of

the Bee. By George Adams. T HE habits of the Pucerons are and this you may pursue through mang

1 so very singular, that I cannot generations. pass them over in silence ; the more Mr Bonnet had repeated experifo, as they are a very curious object ments of this kind, as far as the fixth for the microscope. They are called generation, which all uniformly pre: by various names, the proper one is fented the observer with fruitful virá aphis; that which they are most known gins, when he was engaged in a series by is puceron, though they are some of new and tedious experiments, from times called vine-fretters and plant- a fufpicion imparted by Mr Trembley lice. They belong to the hemiptera in a letter to him, who thus expresies order. The roftrum is inflected, the himself: “ I have formed the design antennæ are longer than the thorax,“ of rearing several generations of folia fome have four erect wings, others « tary pucerons, in order to see if they have none at all: towards the end of « would all equally bring forth young. the belly there are two tubes, from “ In cases so remote from usual cirwhich is ejected that most delicate se cumstances, it is allowed to try all juice called honey-dew.

« sorts of means; and I argued with The aphides are a very numerous “ myself, who knows but that one genus. Linnæus has enumerated thir- « copulation might serve for several ty-three different species, whose trivial “ generations ?” This “ who knows"? names are taken from the plant which perfuaded Mr Bonnet that he had not they inhabit, though it is probable the fufficiently pursued his investigations. number is much larger, as the fame He therefore now reared to the tenth plant is often found to support two or generation his folitary aphides, having three different forts of aphides , the patience to keep an exact account

An aphis, or puceron, brought up of the days and hours of the birth of in the most perfect folitude from the each generation. He then discovered very moment of its birth, in a few days both males and females among them, will be found in the midst of a nume- whose amours were not in the least rous family : repeat the experiment equivocal ; the males are produced on one of the individuals of this fa- only in the tenth generation, and mily, and you will find this second are but few in number ; that these generation will multiply like its parent, foon arriving at their full growth, co

* Ejays on the Microscope; lately published.

pulate

Ixi.

pulate with the females, and that the it happens that the infe&t makes too." virtue of this copulation serves for early an appearance, the greater part ten successive generations ; that all suffer from the sharp weather that u. these generations, except the first, sually succeeds ; by which means, the from fecundated eggs, are produced rose-trees are some years in a manner viviparous, and all the individuals are freed from them. The same kind of females, except those of the last gener. animal is then at one time of the year ation, among whom fome males appear viviparous, and at another oviparous. . to lay the foundation of a fresh feries. Those aphides which stand the fem . In order to give a further inlight verity of the weather feldom come to into the nature of these infects, I their full growth before the month of Shall insert an extract of a description April, at which time they usually be. of the different generations of them gin to breed, after twice cafting off by Dr Richardson, as published in their exuvia, or outward covering. It the Philosophical Transactions, vol. appears that they are all females, which

produce each of them a numerous pro. “ The great variety of species which geny, and that without having interoccur in the insects now under confi. course with any 'male inseat ; they are deration, may make an inquiry into viviparous, and what is equally singutheir particular natures seem not a lite lar, the young ones all come into the tle perplexing; but by reducing them world backwards. When they first under their proper genus, the difficulty come from the parent, they are enve. is considerably diminished. We may loped by a thin inembrane, having in reasonably suppose all the infects, com- this situation the appearance of an ou prehended under any distinct genus, val egg ; these egg-like appearances ad. to partake of one general nature; and here by one extremity to the mother, by diligently examining any particular while the young ones contained in them fpecies, may thence gain some insight extend the other, by that means grainto the nature of all the res. With dually drawing the ruptured membrane this view Dr Richardson chofe out of over the head and body to the hind feet. the various sorts of aphides the largest During this operation, and for some of those found on the rose-trte, not time after, the fore part of the head only as its size makes it more conspi- adheres, by means of something glu. cuous, but as there are few others of tinous, to the vent of the parent. Be. fo long a duration. This fort appears ing thus suspended in the air, it soon early in the Spring, and continues late frees itself from the niembrane in which in the Autumn ; while several are li- it was confined ; and after its limbs are mited to a much shorter term, in con- a little strengthened, is set down on forinity to the different trees and plants some tender shoots, and left to provide from whence they draw their nourish- for itself. ment.

In' the Spring months there appear 1. If at the beginning of February on the rose-trees but two generations the weather happens to be so warm as of aphides, including those which proto make the buds of the rose-tree swell ceed immediately from the last year's and appear green, small aphides are eggs; the warmth of the Summer adds frequently to be found on them, tho' so much to their fertility, that no less pot larger than the young ones in than five generations succeed one ano. Summer, when first produced. It will ther in the interval One is produced be found, that those aphides which apa in May, which cafts off its covering : pear only in Spring, proceed from small while the months of June and July black oval eggs, which were deposited each supply two more, which cast of A the last year's shoot; though when their coverings three or four times,

according

according to the different warmıh of two of which generally make their apo the season. This frequent change of pearance in the month of August, and their outward coat is the more extra- the third before the middle of Sepordinary, because it is repeated niore tember. The two first differ in no often when the infucis come the foon- refpc&t from those which are found in ett to their growth, which sometimes Summer; but the third differs greatly happços in ien days, where warmth from all the rest. Tho' all the aphides and plenty of nourishment conspired. which have hitherto appeared were fer

Early in the month of June, fome males, in this tenth generation several of the third generation which were male infects are found, but not by any produced about the middle of May, mcans fo numerous as the females. after casting off their last covering, The females have at first the same discover four ere& wings much longer appearance with those of the former than their bodies, and the same is obe guncrations, but in a few days their fervable in all the succeeding gencia- colour changes from a green to a yel. tions which are produced during the low, which is gradually converted inSum.uer months, but Itill without a- to an orange before they come to their ny diyersity of sex; for some time be- full growth; they differ also in ano. fore the aphides come to their full cher refpect from those which occur growth, it is easy to distinguish which in Summer, for all these yellow fem will have wings, by a remarkable fulle males are without wings. The male ness of the breast, which in the others infects are, however, still more res is hardly to be distinguished from the markable, their outward appearance body. When the lait covering is re- .readily distinguishing them from this jectes, the wings, which were before and all other generations. When fir folded up in a very narrow compass, produced, they are not of a green co. are gradually extended in a very fur- lour like the rest, but of a reddish prizing manner, till their dimensions brown, and have afterwards a dark are au lait very considerable.

line along the back; they come to The increase of these inseats in the their full growth in about three weeks, Summer time is so very grcat, that by and then cast off their last covering, wounding and exhausting the tender the whole infect being after this of a shoots they would frequently suppress bright yellow colour, the wings only all vegetation, had they not many e. excepted; but after this change to a nemies to re{train them. Notwith- deeper yellow, and in a very few hours Atanding these insects have a numerous to a dark brown, if we except the boaribe of enemies, they are not without dy, which is something lighter colours friends, if those may be considered as ed, and has a reddish cast. The males Such, who are officious in their attende no sooner come to maturity than they ance for the good things they expect copulate with the females, who in e to reap thereby. The ant and the bee day or two after their intercourse witha are of this kind, collecting the honey the males lay their eggs, generally near in which the aphides abound, but with the buds. Where there are a num. this difference, that the ants are con- ber crowded together, they of course Atant visitors, the bce only when flow- interfere with each other, in which ers are scarce ; the ants will suck in they will frequently deposit their eggs the honey while the aphides are in the on other parts of the branches. act of discharging it"; the bees only It is highly probable that the a.. collect it from the leaves on which it phides derive confiderable advantages bas fallen

by living in society; the reiterated In the Autumn three more gene- punctures of a great number of them tations of the aphides are produced, may attract a larger quantity of nutriti Vol. VII, No 39.

ous

bus juices to that part of the tree, or the mother of the next generation; that plant, where they have taken up their the drones are the males, by which abode.

the is fecundated : and that the works

ing bces, or those that collect wax on In the natural history of infects, new the Aowers, that knead it, and form objects of surprize are continually ric from it the combs and cells, which sing before the observer: fingular as they afterwards fill with honey, are we have already shewn is the produc- of neither sex. The queen-bee is tion of the Puceron, that of the Bee known by its size, being generally will not be found to be less so; and much larger than the working-bee of though this little republic has at all the drone. .... . . . . times gained universal esteem and ad- Mr Schirach, a German naturalist, miration, though they have attracted affirms, that all the common bees are the attention of the most ingenious females in disguise, in which the organs and laborious inquirers into nature, that distinguish the fex, and particuyet the mode of propagating their larly the ovaria, are obliterated, or at species seems to have baMed the in- least from their extreme minuteness genuity of ages, and rendered their have escaped the obscrver's eye ; that attempts to discover it abortive ; even every one of those bees, in the earlier the labours and scrupulous attention period of its existence, is capable of of Swammerdam were unsuccessful; becoming a qucen bee, if the whole though, while he was writing his trea- community Mhould think it proper to tise on bees, his daily labour began at nurse it in a particular manner, and fix in the morning, and from that hour. raise it to that rank: in short, that the till twelve he continued watching their queen bee lays only two kinds of eggs, operations, his head in a manner dif- those that are to produce the drones, folving into sweat, under the irre. and those from which the working fiftible ardour of the sun; and if he bees are to proceed. desisted at noon, it was only because Mr Schirach made his experiments his eyes then became too weak, as not only in the early Spring months, well from the extraordinary afflux of but even as late as November. He light and the use of glasses, to continue cut off from an old hire a piece of the longer exercised by fuch minute ob- brood-comb, taking care that it conjicts. He spent one month entirely tained worms which had been hatched in examining, defcribing, and reptes about three days. He fixed this in fenting their intestines ; and many an empty hive, together with a piece months on other parts : employing of honey-comb, for food to his bees, whole days in making obfervations, and then introduced a number of comand whole nights in registering them, mon bees into the hive. As soon as till at last he brought his treatise of these found themselves deprived of bees to the wished-for perfection ; a their queen and their liberty, a dreadful work which all the ages, from the uproar took place, which lasted for the Commencement of natural history to space of twenty-four hours. On the our own times, have produced nothing cessation of this tumult they betook to equal, nothing to compare with it. themselves to work, first proceeding to “ Read it, says the great Boerhaave, the construction of a royal cell, and .consider it, and then judge for your- then taking the proper methods for felf.” Reaumur, however, thought feeding and hatching the brood inclo. he had in some measure removed the fed with them ; sometimes even on veil, and explained their manner of the second day the foundation of one generating : he supposes the queen-bee or more royal cells were to be percei. to be the only female in the hive, and yed; the view of which furnished cese tain indications that they had elected some parts of this veil he was enabled one of the inclosed worms to the love to fee fome of the bees inferting the reignty. The bees may now be left posterior part of their bodies each inat liberty.

to a cell, and sinking into, but continuThe final result of these experi- ing there only a little while. When ments is, that the colony of working they had retired, it was easy to disbees being thus fhut up with a morsel cover a whitish liquor left in the angle of brood-comb, not only hatch, but at of the balis of each cell, which con. the end of eighteen or twenty days tained an egg. In a day or two this produce from thence one or two quecns, liquor was absorbed into the embryo, which have.to all appearance proceed- which on the fourth day assumes its ed from worms of the common fort, worm or larva state, to which the which appears to have been converted working bees bring a little honey for by them into a queen, merely because nourishment, during the first eight or they wanted one.

ten days after its birth. When the From experiments of the same kind, bees find the worm has attained its varied and often repeated, Mr Shirach full growth, they leave off bringing it concludes that all the common work- food, they know it has no more need ing bees were originally of the female of it; they have still, however, ano. sex; but that if they are not fed, lod. ther service to pay it, in which they ged, and brought up in a particular never fail, it is that of fhutting it up manner while they are in a larva state, in its cell, where the larva is inclosed their organs are not developed ; and for eight or ten days: here a further that it is to this circumstance attend- change takes place; the larva, which ing the bringing up of the queen, that was heretefore idle, now begins to the extension of the female organs is work, and lines its cell with fine silk, effccted, and the difference in her while the working-bees inclose it ex. form and size produced.

teriorly with a wax covering. The Mr Debraw has carried the subject concealed larva then voids its excrefurther, by discovering the impregna- ment, quits its skin, and assumes the tion of the eggs by the males, and the pupa ; at the end of some days the difference of the size among the drones young bee acquires sufficient strength or males ; though indeed this last cir- to quit the slender covering of the pupa, cumstance was not unknown to Mess. tear the wax covering of its cell, and Maraldi and Reaumur. Mr Debraw proceeds a perfect infect. watched the glass hives with indefa- To prove further that the eggs are tigable attention, from the moment fccundated by the males, and that the bees, among which he took care their presence is necessary at the time there should be a large number of of breeding, Mr Debraw made the foldrones, were put into them, to the lowing cxperiments. They consist queen's laying her eggs, which gene- in leaving in a hive the queen, with rally happens the fourth or fifth day; only the common or working bees, he observed, that on the first or second without any drones, to see whether day (always before the third) from the eggs the laid would be prolific, the time the eggs are placed in the To this end, he took a swarın, and cells, a great number of bees fastening thook all the bees into a tub of water, themselves to one another hung down leaving them there till they were quite in the form of a curtain, from the top fenfeless; by which means he could to the bottom of the hive ; they had distinguish the drones, without any done the same at the time the queen de- danger of being lung: he then reitopolited her eggs, an operation which red the queen and working -bees to seems contrived on purpofe to conceal their former state, by spreading them what is transacting : however, through on a brown paper in the sun ; after

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