Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/1014

 L I O

L I O

Thefe little infects are a prey alfo to a fort of worm hatched from the egg of a two winged fly. This has no legs, and is of feveral colours. See the article V ER-puceron. Though thefe Uon-ptuerons be all hexapodes, yet they are of different origin ; fome being produced from the eggs of a four winged fly, others from thofe of a beetle. As the formica leo has two horns, the extremities of which ferve him by way of mouths, our Hon-puceron has the fame kind alfo ; but as the former of thefe infects can only move back- wards, and is forced to make fnares for his prey, not being able to hunt it ; this creature runs very nimbly in the common way, and feizes its prey, without having recourfe to fuch ftratagems.

The body of the lion-pucerm is longer than that of theyir- rtnea ho, and is flat ; the breaft is the thicken: and broadeft part of it, and from this it gradually tapers off" to a point at the tail. It has two legs fixed to the breaft, the other four to the anterior rings of the body, and when it moves, the poflerior end of the body ferves it in the place of a feventh leg, for it always bends it downward, and draws it along the furfacc it walks upon. The back of this crea- ture is not fmooth or glofly, but is every where rough, and full of wrinkles, and feems as if every ring of it was compofed of feveral other fmaller rings. This is the general defcription of the creature, treating of it in a general way, thefe characters Suiting all the kinds of it. There are others, however, by which the whole clafs may be divided into three principal kinds. The moft common fpecies is diftinguifhed by a peculiar character, which is, that it is hairy at the fides, or, to fpeak more determinately, every ring of the body has on each fide, juft in that part where the back and the belly meet, a flefhy tubercle, or protuberance, which carries a tuft of ten or twelve hairs. There are of this kind of feveral Sizes and colours, and the moft frequent are of a chefnut, or yellowifh hue on the back, and white on the belly. Thefe are much more voracious devourers of the pucerons, than the worms which feed on them, A fmall pucer -on, Seiz- ed by one of them, is eaten in an inftant, and the very largeft is not the work of half a minute for them. Thefe creatures are very fmall when firft produced from the egg, and yet they immediately begin to feed. They are fo ra- venous of food alfo, that whenever they can they catch and eat one another. But as the pucerons, among which they live, are eafier to be caught, they ufually efcape one an- other's fury pretty well ; unlefs where there is a fcarcity of the pucerons, or when they offend one another. Mr. Reaumur put twenty of thefe creatures together into a box, where they had no other food, and where they could not efcape one another, and thefe were very foon reduced to three or four. It is eafy to conceive that a creature, which feeds fo very faft, muft foon arrive at its full growth ; and this is the cafe with thefe animals, for within five or fix days of their being hatched from the egg, they are ready for their final transformation, or the putting on the form of the ani- mals to whofs eggs they owed their origin. In order to this, the creature leaves the place where he has hitherto fed, and Seeks the folds of a leaf, or fome other fuch convenient re- ceptacle, where it fpins a web of very fine filk, every way furrounding its body with it, and under this cover pafles the flate of a nymph or cbryfalis. The filk of this web is not only very ftrong, but the threads are very clofely laid toge- ther, fo that it is much firmer than the webs of any of the caterpillar kind. It is of a roundifli figure, and is fome- what fmaller than a pea.

This round figure is owing to the form into which they roll up their body, which ferves as a mould for it ; and the orifice, out of which the filky matter is produced, is at the extremity of the poflerior part of the body. The creature continues in this ftate about three weeks, if it be in the beginning of the fummer that it goes into it ; but if toward autumn, it remains in it all the following winter ; and is afterwards, in fpring, feen to come out in the form of a very beautiful fly, of a remarkably large fize, in proportion to the creature it is produced from, and the web out of which it comes. It is a very long bodied one, and much refemblcs the libella or dragon fly, only that its wings are larger in proportion to its body : thefe wings are of a moft delicately fine ftructure, the fineft gawfe being coarfe and thick in comparifon to them. Thefe, when the creature is at reft, are placed in an angle over the body, and form a fort of canopy or tent for it, but they are fo perfectly trans- parent that the body is eafily fecn through them. The body and breaft are all green, and that of a very beautiful tinge ; but the moft remarkable beauty of this creature is its eyes ; thefe are large and prominent, and are of a fine gold colour, and of greater luftre than the moft highly polifhed metal. The eggs of this fly are a very Angular object, and cannot have efcaped the eye of any perfon who Is converfant among the infects which live on trees ; though of the many who have feen them, perhaps few or none ever found what they really were. It is common to fee on the leaves, and pedicles oi' the leaves of the plum tree, and feveral other trees, as alfo on their young branches, a number of long and flendcr

filaments, running out to about an inch in length, and betttg of the thicknefs of a hair ; ten or twelve of thefe are ufually 1 feen placed near one another, and a vaft number of thefe clufters are often found on the fame tree. The end of each of thefe filaments is terminated by a fort of Swelling or tu- bercle of the fhape of an egg. People who have obferved thefe, have generally fuppofed them to be of vegetable origin, and that they were a fort of parafitical plants, growing out of others, as the mifletoe, moifes, csV. from the oak and other trees. They very much refemble in figure thofe fpecies of mouldinefs, which Malpighi and others have figured under the fhape of little mufhrooms, only they are much larger than thofe little plants, and bear the heat of the fun and other accidents uninjured, which would deftroy the tender plants of that kind. There is a time, when thefe egg-like balls, which terminate every one of thefe filaments, are found open at their ends, and in this ftate they very- much refemble flowers, and they are in this ftate figured by fome authors under the name of flowers of a Singular kind, found on the leaves of the willow. Alt this, however, is wholly erroneous, and the purfuing the hiftory of our lion pucerons, Shews their true origin to be from the fly of that creature. What thefe authors took for flowers of the wil- low were only the eggs of this fly, oat of which the young animals had been hatched, and had made their efcape. The leaves and branches on which thefe eggs are found, are ufually feen covered over with the pucerons ; and the crea- ture providing a place where her young Shall find nourish- ment as foon as hatched, places her eggs in the midft of thefe harmlefs and defencelefs animals, fixing each on a flen- der pedicle, yet fufficiently ftrong to fupport its weight. If thefe eggs be nicely examined, a worm may be difcovercd in them while yet whole ; but the moft certain way of judg- ing of them, is, to put feveral of them into a box, in which cafe every one of them is found at a proper time to hatch, and to give an infect; which, when viewed by the micro- fcope, appears plainly to be a Hon puceron in all its parts, and requiring only increafe in fize, without any change of fhape, to be one of thofe we have already defcribed, as feeding fo voracioufly on thepucerons, Reaumur's Hift. Inf. Vol. 6, p. 142.

The manner in which the parent fly plapes her eggs in this Singular way on the trees, is a fobject that greatly excited the curiofity of Mr. Reaumur. He often watched the ani- mals in vain, in order to fee them employed in it ; and, in fine, fhut up feveral of them in boxes. The confequence of which was, that they fixed their eggs on long pedicles, to the fides of the box, in the fame manner, that they be- fore had to the fides of the branches, or leaves of trees ; but he never could find them employed about it. The manner in which he fuppofes it done, however, appears very rational, and is as follows :

The egg is fuppofed, while in the body of the infect, to be covered with a tough glutinous matter, capable of drying very fuddenly in the air. The creature, when the egg begins to come forth, applies the extremity of it to Some Solid body, as a leaf, or ftalk of a plant, and then drawing herfelf away 8 there follows a thread or filament of this vifcous matter, which is fattened at one end to the leaf, and at the other to the egg in her body. When fhe has drawn this out, ta an inch in length, fhe flops a moment, and the whole will harden into a folid matter; and, on her next motion, will draw out the egg from her body, and will become a pedicle to it. In this condition it will remain till the egg is hatched, and then the young infect needs only to defcend downward on the leaf, on which the pedicle is fixed, and it will find itfelf in the midft of plenty of food.

Mr. Piftorius found a number of thefe eggs on a cherry ; he diftinguifhed them very plainly to be eggs^ and preferved them till they hatched. The young ones died with him for want of nourifhment ; but, by his figures of them engraved from the microfcope, it appears very plainly, that they were the very infect we havedefcribed under the name of the Uonpuceron. The fecond kind of thefe infects differs from the firft in no other particular, but that it has no tufts of hairs on its fides, and in that it is not of a yellow or brown colour as thofe of the firft kind are, but of a dufky grey. This after it has lived its proper time in this ftate, becomes alfo a chryfalis- of a round figure, and of the fize of a pea, enveloped in a. web of filk of its own Spinning. After the creature has remained a month in this ftate, it comes forth in the form of a four winged fly ; which, however, is very different from that produced by the firft kind. Its body is oblong, but lefs long than that of the former ; and its wings are ex- tremely different, being as remarkably opake in this, as they are remarkably tranfparent in the other; the outer wings are of a brownifh red, and the inner ones of a yellowifh colour ; the outer ones are confiderably the moft opake and thick, and indeed they not a little refemble the upper wings of the grafhoppers. Reaumur's Hift. Infect. Vol. 6. p. 139. The third kind of thefe infects is very different from the other two. It is considerably fmaller and thicker bodied, the others being both very flat. This feeds on the pucerons in the manner of the others, but it is fo voracious, that

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