Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/177

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when fmaller, the help of glafles will always di'fcover tliem ; the place where they are fituated being rendered the more confpicuous and obfervable by two brown crefcents placed round them. ,

Thefe worms may be properly enough titled the inhabitants Of animal "-alls, fmce the tumors which contain them are truly analogous to the galls of the oak and other the like ve- getable excrefcences. r4 The hole in thefe tumors is not only ufeful to the animal for a breathing place, but it has another not lefs necefiary ufe; which is to let off a quantity of abundant matter formed in the tumor, which would, if confin'd there, occafion a large abfeefs and choak and deftroy the animal. If thefe worms were endued with the qualities of thofe of the common £efh-fly, and had hooks at their head-part, to tear and pull the flefli in pieces, the creature who had thirty or fbrtv of thefe gnawing devouiers in its back, preying upon its flefn at once, would be in a very miferable ftate : but this is by no means the cafe, the creatures have no organs- to tear its flefh with, they only live on the matter found in the abfeefs, and cive the creature no great pain ; being only like fo many tents kept in a wound necefiary to be preferved open, or fo many peas in iflues.

The worms may at any time be diilodged from thefe tumors by a moderate preffure, and made to come out at the hole of the tumor. This, tho' it appear confiderably too little, yet anfwers the purpofe; as the body of the worm well enough bears preffure, and it is only neceffary, in order to get them out whole, to renew the force upon the tumor, for the pufh- ing out every feparate ring of its body. While thefe worms are young, they are white, like thofe of the common flefh-fly ; but when they grow towards their full fize, they become fomewhat brown They are of different iizes, as is ufual with the worms of other flies; thofe which are to give the female fly being always the larger, and thofe which give the male the fmaller. The larger of thefe are con- fiderably more than an inch long, and more than half an inch thick in the ful left part of their bodies.

They have nothing very remarkable in their fhape ; their an- terior part is fomcthing fmaller than their pofterior, and they have no legs. They arc compofed of eleven rings, counting that for one where the mouth is placed ; and of thefe the eighth is the largeft. Thefe rings are not quite circular, being fomewhat flatted on one fide; but what is moft remarkable is, that the flatter fide is the back, and hence the creature is, con- trary to the ufua! cuftom of thefe infects, hollow, as it were, on the back, and convex on the belly : and there is a good reafon for this, fince, as all the other worms which are deftined to crawl upon a flat furface ought to have their bellies flat, that they may touch it in as many points as may be, and the creature be by that means kept fleady, fo this creature which inhabits the concave furface of a cavity, ought, in order to have its belly touch in as many points as may be, the furface it has to crawl upon, to have it, as it is found, tolerably convex.

The worm has fix longitudinal furrows on its back and fides, which interfering the channellings of the rings, make its fur- face very rough and uneven: but befides this, the whole in- termediate fpaces appear chagrined, and when examined by the microfcope, are found to be covered with yellowifh prominent triangular bodies.

As this worm has no legs, it is eafy to determine, that thefe innumerable fmall protuberances were allotted it, in fome fort, to fupply the place of them, to fix itfelf by to any place, and to affift it in moving ; and may, befides this, ferve to the con- tinual irritation of the infide of the tumor, and keep up the feparation of a matter necefiary to the creature's life. When the worm has attained its full growth, and is to make its way out of the hole in the tumor, this, as yet, appears much too fmall to give it paffage. Nature, however, has inftrucled this worm to do what our furgeons pracYife on a like occafion; when they are to open the orifice of a wound, they often do it by means of large tents ; the creature inclofed in this tu- mour makes the hinder part of its own body fupply the office of a tent on this occafion : for three or four days before it is to make its way out, it forces its hinder part into the orifice, and keeps it there a longtime; then takes it back, and after- wards thruits it thither again, and continues without inter- mifllon repeating this operation; and when, by this means, the hole is fumciently enlarged, it crawls out flowly, with its hinder part backward.

As foon as it is out of its habitation, it falls to the earth, where it crawls flowly about till it finds a place where it may reft, to go through its feveral changes, under a ftone, or in any quiet place.

Sta?,s and fome other animals arc fubjeel to thefe worms in the fame manner as oxen, and the feveral ftages they go through in the tumors on thefe animals are the fame with thofe of the ox.

When they have fixed upon a place to reft in for their chan- ge, they Iofe all motion, and their fkin becomes black and hard, and makes a (hell for their remaining in through their futceeding changes.

When the time of the egrefs of the fly is'come, it appears a two-winged one indeed, but fo extremely like the humble- bees of a middling fize, that it is not eafily to be diftinguifh- ed for what it is : one humble-bee cannot be mure like ano- ther, than thefe flies are to that fpecies of them ; their bodies are as fhort, all of the fame colours, and are even more

nairy.

This fly, clofely examined, appears to be of the fecond clafs* and to have a mouth without teeth or lips, arid its mouth very fmall. The antenna? are fhort, rounded at their ends, and of a gloffy hue. The reticular eyes are of a deep chefnut colour. -

The female has, in the under and hinder part of her body, a cylindric tube, which fhe can thruft out at pleafure, and which is the inftrument with which fhe pierces the fkin of the ani- mal, to depofit her egg. Reaumur Hift. Infect V0I.4.P.503, feq. to 537.

Ox-gang^ or Oxengate. A term iifed in Scotland for a por- tion of arable land, containing li acres. Tr. Pract. Geom. P. 86. S ^

OXALME, in the materia medica of the antients, the name of a compofition of vinegar and b:ine, made by a folution of fea-falt in water. This was ufed externally in ulcers, and fuppofed of great fervice againft the bites of venomous animals, and for the curing childrens fcabby heads. It was alfo ufed as a ftyptic poured into wounds, and was fometimes given warm in clyfters ; but thefe were always followed by thofe of milk.

OXEL/EUM, a word ufed by many authors to exprefs a mix- ture of vinegar and oil, for outward application, in cafes of bruifes and other injuries.

OXUCI^E, in natural hiftory, the name of a genus of foffils of the clafs of the fcknita:, but of the columnar not the rhom- boidal kind. The word is derived from the Greek <$?% fharp, and x\uv a column ; and expreffes a body of a columnar form, and pointed or fharp at the ends. The fdenita of this genus confift of fix equal plane?, having their top or bottom no broader or more deprefled than the others ; and in this differ- ing from the ij'chnambluces, or flatted columnar felmita^ as they do from the ifambluces or cryflaliform^ but broken ended ones, by having their ends naturally tapering off to a point. SeeTab. of Foffils, Clafs 2. BiiH Hift. of Foffils, p 121. The bodies of this genus, like thofe of the other genera of the columnar feknita?, are liable to a longitudinal crack in their middle; and this fometimes includes a little clay, in form of an ear of grafs. See Selenites.

Of this genus there are only two known fpecies : 1. A fine kind, with thin flakes and tranfverfe filaments, found in the clayey banks of the river Neu, near Peterborough, in Nor- thamptonfhire; arid, 2. A dull kind, with thick plates and longitudinal filaments. This is not uncommon in Yorkfhire, and lies fometimes in a yellow, fometimes in a blue clay. Hill's Hift. of Foff. p. 141, 142.

OXYA, in botany, a name by which many authors, efpecially the Greeks, have called ihefagus or beech-tree. J. Bauhhi, Vol. I. p. 117.

OXYBLATTA, among the antients, is ufed to denote a bright and gloffy kind of purple colour. Hoffm. Lex. in voc.

OXYCEDRUS, in botany, a name given by fome authors to the cedrus folio cuprejfi, or the herry-bareing cedar. Chabraus 9 p. 72.

OXYCOCCUS, in botany, the name of a genus of plants, the characters of which are thefe: the flower is of the rofaceous kind, being compofed of feveral petals, arranged in a circular form ; the cup finally becomes a roundim fruit or berry, which is divided into four cells, containing roundifh feeds. The fpecies of oxycocats enumerated byMr.Tournefort,are thefe : 1 . The common oxycoccus, or moor-berries ; and, 2. The broad- leaved oxycoccus. "Tourn. Inft. p. 65;.

OXYGARUM, a word ufed by the antients to exprefs a mix- ture of vinegar and garum, which is a pickle for the preierv- ing fifh, or a fimple mixture of fea-falt and water.

OXYGLUCA, a word ufed by the antients to exprefs a liquor made of a mixture of honey, water, and vinegar. The com- mon way of making it was by macerating the combs, after the honey was preffed out, in water ; and then adding a fmall portion of vinegar, to give it a tartnefs. It was fometimes made without the addition of the acid, and made a weaker fort of mead, ufed as a common drink in hot weather. Galen fays, it was the fame with the apometi.

OXYLIPES, a word ufed by fome authors as a name for bread, which has a mixture of vinegar in it ; intended fometimes mr eating, fometimes for medicinal ufes.

OX Y MY R SINE, in botany, a name by which fome authors have called the rufcus, or butcher's- broom.

OXYPHCENiCON, in botany, a name ufed by fome authors for the tree whofe fruit is the tamarind of the (bops. Mant. Exot. p. 10.

OXYPYCNf, o£wrwwoi, in the antient Greek muuc, was a name given to fuch chords as formed the higheft founds of they/>/^,i. There were five oxypycm in the fcale. See the articles PvCNJ and Spi^sum. OXYREGMiA, a word ufed by the antients to exprefs acid eructations.

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