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kind ; others appear to be extremely fingular productions of the trees on which they arc produced and could not at firft tight be fuppofed to be galls: of this kind is the hairy or fila- mentous gall of the briar, or wild rofe, called by the French cheveleau, and by the medical writers bedeguar. The oak af- fords a gall of a very fingular ftructure, refembling the fquammofe cup of a flower of fome of the headed plants, as the jacea or the like;, or to exprefs it by a more known thing, the common artichoke, the French from this call it the ar- tichoke gall ; other {pedes are covered with longer or ihorter fpines or protuberances, ending in a more or lefs Iharp point; thefe are called the prickly galls ; and the com- mon galls of the oak brought from the Levant, and ufed in dying, are diiUnguifhed by the workmen, by the name of rough or prickly galls, from the European ones, particularly thi,fe of France j which are ufually very round, and of a per- fectly fmoolh and even furface, and glofiy on the outiide. lit fide thefe there is a very beautiful fpecies of galls that al- ways grow in the figure of the common mufhroom. THelclTer diftinctions are too minute to be entered into here; but the curious will find them accurately treated of in the ex- cellent trentife of Malpighi on this nibject, to which the accounts given by Pveaumur are a fort of commentary and fupplement. Obfervations fhew that there is no part of a plant on which galls are not fomctimes formed j the young italks feem the moft natural parts, and are the moft commonly or all others affected by them ; but they are alio found on the leaves, the pedicles of the leaves, the eyes or buds of young leaves, the buds of flowers, and the petals of full blown flowers, and finally on the roots. Every gall ferves for the nidus of fome one or more infects, and there are vaft variety of thefe fmall animals which inhabit them, even thofe of different clalVes at times forming them ; and it feems equally certain^ that the fhape and ftructure of the gall, depend on the in- fects which form it. This appears very evident from this, that the leaves of the fame tree will fometimes afford galls inhabited by different infects, and fome of thefe will be hard and woody, while others are foft and fpungy. We may al- ways fee from the outer furface of a gall, what is its ftate within : If it is whole throughout, and there appear no perfo- rations or apertures, it is a certain proof that the animal which occafioned it is yet within it j but if there are found one or more holes in the furface, penetrating into the fub- ftance, thefe are the apertures through which the infect or infects have efcaped, and the gall will be found empty. It is often neceflary to ufe a magnifying glafs on this occafion, in order to determine with any degree of certainty ; becaufe many of the infects which inhabit galls are fo fmall that the apertures through which they have efcaped are not vifible to the naked eye. When, however, the glafs does not fhew any fuch perforations, on opening the gall with a knife, we always find the infect, or infects within, either in their worm ftate, or in that of the chryfalis; for the generality of the inhabitants of galls are to undergo a metamorphofis, being worms, maggots, or caterpillars in their firft ftate, and be- coming finally either four winged or two winged flies, of the firft fort of which there are very numerous varieties; or elfe butterflies of peculiar kinds* or finally beetles. Reaumur Hilt. Inf. Vol. 6. p. 186.
As the origin of thefe creatures is from the eggs of the pa- rent infect in this form, we find accordingly all the varieties of worms and maggots within them j fome having legs, fome not, fome having hard and fcaly heads, others only foft and membranaceous ones ; and finally, we often find creatures different from all thefe in them ; thefe have been deftroyers and murderers, having killed and eaten the proper inhabitants and feized on their habitations.
It was an opinion of Malpighi, that all the galls on the vari- ous parts of vegetables had but one origin, which was from the puncture of an ichneumon fly, who depofited her egg there for her future progeny. It is pretty certain indeed, that all thefe unnatural productions of vegetables are owing to injuries done by infects ; but various other creatures befidc this fly arc capable of doing them, and Mr. Reaumur has ob- ferved that a viviparous creature, the pulex arboreus, or puce- ron, is frequently the occafion of them. Thefe excrefcences of trees are of fuch a diverfity of figures, that they can never be the fubject of a regular defcription ; fome are wholly irregular in fhape, while others reprefent fruits or flowers. They may In general be divided, however, into three claffes. Thofe of the firft clafs have only one cavity, which contains one infect and never more. Thofe of the fecond contain many infects all living together in the fame cavity. And finally, thofe of the third clafs arc divided within into feveral cellu- lar cavities ; in each of which their lives one worm or other infect, which has no fociety with, nor entrance into the dwellings of the reft. Some galls arc found refembling ap- ples, others cherries hanging on long ffalks, others clufters of grapes, others pine cones, and others the rough fruit of the chefnut tree, containing the chefnuts ; they are found prin- cipally on trees,, though not unfrequcntly on plants. It is cafy to fee by the outfide of thefe galls, whether they actu- ally contain an infect at the time of infpection, or whether they only have contained one which is fiucc efcaped. If they Sufpl. Vol. L
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are whole on the furface, it is a proof that the creature Is yet within them, waiting the time of its change ; but if they have a hole in any part, they (hew that the creature
- has paffed into its perfect ftate, and has efcaped out at that aperture. Thofe gaUs which have only one internal cavity, have only one aperture ori the furface, whether it be only. one or more of the animals that is to cfcape at it ; hut if there are feveral cells, each inhabited by a feparate infect, then there are on the furface f> many apertures» one corre- sponding to every cell. All the inhabitants of thefe galls, do riot however wait the time of their change within them ; but fome fpecies crawl out when their change is approaching, and pafs their previous ftate of reft in the form of nymphs elfc- where. It is not unfrequent alfo to find a two winged fly, and a four winged one, both coming out of the fame gall. It is eafy to fee that thefe could not be produced of worms hatched by the eggs of the fame parent. One of them only is the proper inhabitant of the excrcfccnce 4 whole origin is from the puncture of its parent fly : the other is an interlo- per, and an enemy, who often cats up the proper inhabi- tant, and then comes out alone as if the whole gall had been made for him ; but if the proper inhabitant has by any acci- dent efcaped, they both come out, either together, or fuc- ccinvely according to the time allotted by nature for their re- maining in their feveral ftates. Reaumur. Hift. Inft. Tom. i. I he galls which have only one cavity, are ufually inhabited by a pfeudo eruca, or baitard caterpillar ; but it often hap- pens that the carnivorous worm of fome other fly, makes its way into the gall, and the proper inhabitant is not known from the ftranger on opening the excrefcence. This is a mifehief that often happens in the fweet fcented hairy gall of the wild rofe, called bedeguar in the fhops. From thefe, though pro- duced only by the puncture of one fpecies of fly, and meant for the reception of its young, it is common to fee feveral different fpecies produced from the worms of other invaders* fly out at the time of their hatching, from the chryfalis ftate. It is not eafy to find out among thefe, which is the proprietary of the gall, and which are the invaders of his territory ; but the gold colour'd fly, admired by many for its beauty, which often is feen to come out from thefe galls, is not the proper inhabitant ; but is produced from a worm, which is a general tyrant and devourer of whatever it meets with lefs or weaker than itfelf in this ftate. Mr. Reneaume in the year 1711, communicated a difcovery of the common oak galls, being a febrifuge not inferior in many cafes to the Peruvian bark, and greatly preferable in many, as wanting fome of its ill qualities. He found it a certain remedy in all intermittent fevers, and that it required to be given in much fmaller dofes than the bark, and its ufe to be continued a much fhorter time ; he is not fo fond of his difcovery how- ever, as to deny the fuperior merit of the bark in fome cafes, but allots to each its peculiar fphere in the following manner. He fuppofes that fevers in general are caufed either by the fharphefs of an indigeftcd chyle, occafioned by the fibres of the ftomach not having done their office ; whether through over tenfion, or too great a relaxation, or by there not beino- a due quantity of bile, mixed with that chyle to attemperate, and take off its acrimony. In cafes where the mifehief is ori- ginally owing to a relaxation of the fibres of the ftomach > the galls by their aftringency work on the fibres, and re- ftore them to their due tone ; therefore in thefe cafes the Falls are to be preferred to the bark. But in thofe which proceed from a want of a due quality of the bile in the admixture of the juices, the bark he acknowledges is to be preferred, its bit- ternefs producing the fame good effect in the chyle that the bile itfelf would. Some of the French academicians tried this with all the fuccefs the difcovercr afcribes- to it, and fome with lefs, the fever having been found to return afterwards and then to yield only to the bark. Thefe gentlemen however are of opinion, that the galls very well deferve to be continued in; practice, as there is often much good done by them, and they have the advantage of not being attended with any ill confequences. In general, galls are found to be very aftringent, and good under proper management in diarrhoeas, dyfenteries, and he- morrhages of all kinds. They have alfo a great virtue as a fe- brifuge, and are often found to cure an intermittent. In, fevers half a dram or more of the powder of Aleppo galls may be given for a dofc. They are alfo ufed externally as a ltrcngthner, and aftringent : a decoction of them is applied with fucccls by way of fomentation in procidentia of the anus, and has been injected in the fluor albus with great fuccefs. Galls may be made a very ufeful teft for iron in the feveral fpecies of vitriols, for it Is certain that an infufion of galls will become black with a folution of any vitriol that contains iron, and not at all fo with fuch as contain only copper, as the common blue vitriol and the like.
Box Galls, in natural hiftory, the name given by authors to a very fingular kind of galls, of a conic figure, with a conic top, or cover refembling a wooden box, and enclofing a white worm in the manner of the other vegetable lodgments of the fame kind j this fort of gall is found only on the leaves of the lime tree. It is common to obferve the leaves of this tree in the month of July, to be pierced throug'i with feveral round botes of about a tenth gf an inch in diameter, and n B a 5
