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tance be considered as the effect of emerged into day, we thought our enthusiasm ; a whole day may be spent felves 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 fuffered any disaster them can excell it, is the only motive except extreme fatigue. The air is that has prompted me to publish this moist without being noxious; it is description, for the exactness and aus even friendly to weak lungs. When thenticity of which I shall be answer we left this place of enchantment, and able.
Account of the Infects called Aphides, and Remarks on the Natural History of
the Bee. By George Adams. HE habits of the Pucerons are and this you may pursue through many
so very singular, that I cannot generations. pass them over in silence ; the more Mr Bonnet had repeated experie fo, as they are a very curious object ments of this kind, as far as the sixth for the microscope. They are called generation, which all uniformly preby 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 exprefíes order. The roftrum is infected, 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 bave 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 persuaded 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 fupport 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 róus 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
pulate * Ejays on the Microfcope; lately published,
pulate with the females, and that the it happens that the infect 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 uthese 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 some males appear viviparous, and at another oviparous. to lay the foundation of a fresh ferie3. Those aphides which fand the few - In order to give a further inlight verity of the weather feldom come to into the nature of these insects, I their full growth before the month of Shall insert an extract of a defcription April, at which time they usually be. of the different generations of them gin to breed, after twice calling off by Dr Richardson, as published in their exuvia, or outward covering. It the Philosophical Transactions, vol. appears that they are all females, which lxi.
produce each of them a numerous pro“The great variety of species which geny, and that without having interoccur in the insects now under confie course with any 'male infect; they are deration, may make an inquiry into viviparous, and what is equally fingutheir particular natures seem not a lit- 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 insects, comthis situation the appearance of an oprehended 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 fome insight extend the other, by that means grainto the nature of all the ref. With dually drawing the ruptured membrane this view Dr Richardson chofe out of over the head and bodyto the hind feet. the various forts of aphides the largest During this operation, and for some of those found on the rose-trte, nog time after, the fore part of the head only as its size makes it more confpi- adheres, by means of something glu. cuous, but as there are few others of tinous, to the vent of the parent. Befo long a duration. This fort appears ing thus fufpended in the air, it soon early in the Spring, and continues late frees itself from the membrane 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 streogthened, is set down on fornity to the different trees and plants fome 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 role-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, fmall 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 finit produced. It will ther in the interval One is produced be found, that those aphides which apin 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 fupply two more, which cait off on the last year's fiost; though when their coveringstilte or four times,
eccording to the different warmth of two of which generally make their
ap. the scafon. This frequent chanye 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 more tember. The two first differ in no often when the infects come the foon- respect from those which are found in eit to their growth, which sometimus Summer ; but the third differs greatly happens in ien days, where warmth from all the rest. Tho' all the aphides and plenty of nourishment conspired. which have hitherto appeared were fe,
Early in the month of June, some males, in this tenth generation several of the third generation which were male insects are found, but not by any produced about the middle of May, means fo numerous as the females. after casting off their last covering, The females have at first the same discover four erect wings much longer appearance with those of the former than their bodies; and the fame is ob- generations, but in a few days their fervable in all the fucceeding genera- colour changes from a green to a yel. tions which are produced during the low, which is gradually converted inSummer months, but Itill without a- to an orange before they come to their by diversity of sex; for some time be- full growth; they differ alfo in anofore the aphides come to their full ther refpect from those which occur growth, it is easy to distinguish which in Summer, for all these yellow fey will have wings, by a remarkable fulle males are without wings. The male ness of the brealt, which in the others infects are, however, still more res is hardly to be distinguished from the markable, their outward appearance body. When the lalt covering is re- readily distinguishing them from this jecte, the wings, which were before and all other generations. When firit folded up in a very narrow compafs, produced, they are not of a green coare 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 at lait very considerable.
line along the back ; they come ta The increase of these infe&ts in the their full growth in about three weeks, Summer time is fo very great, that by and then cast off their last covering, wounding and exhausting the tender the whole infe&t being after this of a fhoots 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 retrain them. Not with- dceper yellow, and in a very few hours Itanding these insects have a numerous to a dark brown, if we except the botribe of enemies, they are not without dy, which is something lighter colourfriends, if those may be considered as ed, and has a reddish cast. The males luch, who are officious in their attends no sooner come to maturity than they ance for the good things they expect copulate with the females, who in to reap thereby. The ant and the bee day or two after their intercourse witla 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, Itant visitors, the bee only when flow- interfere with each other, in which ers are scarce ; the anis will fuck 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 considerable advantages bas fallen.
by living in society; the reiterated . In the Autumn chrce more gene- punctures of a great number of themr sations of the aphides are produced, may attract a larger quantity of nutritie Vol. VII, No 39. Co
ous 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 work
'ing bces, or those that collect wax on In the natural history of infe&ts, new the fowers, that knead it, and forin objects of surprize are continually ri- 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-bce is tion of the Puceron, that of the Bee known by its size, being generally will not be found to be less fo; 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 baffled the in- least from their extreme minuteness genuity of ages, and rendered their have escaped the observer'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 queen bee, if the whole though, while he was writing his treae community should 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 dis- those that are to produce the drones, folving into sweat, under the irre- and those from which the working fistible 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 glaffes, to continue cut off from an old hire a piece of the longer exercised by fuch minute ob- brood-comb, taking care that it conjucts. He spent one month entirely tained worms which had been hatched in examining, describing, and reptes about three days. He fixed this in fepting 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 foon as rill 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 Commencemnent of natural history to space of twenty-four bours. On the our own times, have produced nothing ceffation 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 inclohe 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 perceito be the only female in the hive, and yod ; the view of which furcished ces tain indications that they had elected some parts of this veil he was enabled one of the inclosed worms to the loves 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 continue The 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 thas fhut up with a morsel cover a whitish liquor left in the angle of brood-comb, not only hatch, but at of the basis of each cell, which conthe end of eighteen or twenty days tained an egg. In a day or two this produce from thence one or two queens, liquor was ablorbed into the embryo, which have to all appearance proceed- which op the fourth day affumes 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 attendo 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, effected, 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 cion 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 infeat. watched the glass hives with indefa- To prove further that the eggs are tigable attention, from the moment fecundated by the males, and that the bees, among which he took care their prefence is necessary at the time there Thould be a large number of of breeding, Mr Debraw made the fol, drones, 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 swarm, and cells, a great number of bees fastening hook 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 senseless ; by which means he could to the bottom of the hive; they had diftinguith the drones, without any done the same at the time the queen de- danger of being stung : he then reitoposited 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