Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/464

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It is to be added alfo, that thefe {hells have fubfided, not in

water, but in a thicker fluid, cornpofed of mud and water, and this has kept them more afunder than common water alone would have done; and we mall find, on examining the bowels of the earth, that though the (hells, in the fame mafs of earth, or ftone, are generally principally of one kind, yet they are neither always fo, nor perfectly fo, but that often they are confufedly blended among other kinds, and more often have fome few of other fpecies blended among them ; as a few cockle- fhells might be among the pebbles, in the familiar inftance mentioned above, and by fome particular accidents, even in that cafe, the whole kt of bodies, excepting the very lighted, might happen to be blended together.

The mountains of Sicily afford fome few gloffopetra;, or fnakes-tongues, but they are few in number, and worfe pre- pared than thofe of the ifland of Malta ; which is probably owing to the high ground of thofe mountains being lefs like- ly to receive the refufe of the fea, and its foil, which is fandy, being lefs fitted to prefcrve them when the;e, than* the marl, of which the ifland of Malta confifts. The echini marini, or fea eggs, and their fpecies, which are very frequent among the ferpenis-tongues of Malta, all lie upon the furface of the ground, or near it ; whereas the gloffopetra lie deeper, though at no great depth. This is a plain effect of all thefe things having been really animal bodies, and having floated in the mud, of which that ifland was formed; for in this it could not be otherwife, but that the gloffopetra, or ferpents-totigues, beinp" heavy, would fub- fide in the water, while the light (hells of thefe other ani- mals would float on, or near the furface. The opinion of thefe bodies growing from feminal princi- ples, is a!fo greatly weakened by the fituation of them in the earth. If they grew from feeds, as plants, we (hould doubtlefs fee them, like plants, all bending one way, the points of all upwards, and their roots downward ; but on the contrary, both in the ifland of Malta and elfewhere, thefe things are found in the moft different directions imaginable ; fome with their bottoms upwards, fome downwards, fame horizontal, and others in all the intermediate angles. Some have fuppofed the gloffbpetra, in particular, to grow from roots in the earth, becaufe they ufually have roots different from the other parts, and becaufe they (tick very firmly i the earth at thefe roots, but are very eafily loofened in any other part. It is certain indeed that thefe parts, at the bot- tom of the gloffopetra, are their roots, and that their fpungy texture was intended for their taking in nourishment ; but this was their ufe when in the head of the fifh, not when in the earth ; and the reafon of their adhering more firmly to the earth in this, than in any other part, is only that they are more fpungy and porous here, and that in other parts, where they are fmooth and even, the earth can have no hold of them ; but where they are thus rough, as they fub- fided with a moift earth like mud about them, they natu- rally become connected ftrongly to it in drying, -as part of it was received into their pores, and not broken from the reft, till by forcing them out afterwards. Philof. Tranf N°2ia. p. 189.

Some affirm that" the gloffbpetra are natural cry ftallizat ions of fait, and that to this their regular figure is owing; but it is to be anfwered, that their figure is not fo regular as thefe obje£lors feem.to fuppofe, but that there are as many different (hapes of them as there are of teeth, in the different parts of the jaw of the fame (hark, or in the jaws of different fpecies of (harks now found living ; and if they were cryf- tallizations of fait, the whole cryftallization would be of one and the fame furface and texture; which is not the cafe, fince the root, as before obferved, is always very dif- ferent from the body of the tooth, and the fubftance diffe- rent in even the various parts of the body. Salts are falts throughout, and a ruby, a cryffal, or a diamond, is the fame in all its parts ; but this is not the cafe in the gloffo- petra, but they are cornpofed of a cortical and a medullary part, like the teeth of living fharks : and it is to be obferv- ed, that when any of thefe gloffbpetra: are found broken, as they frequently are, the fracture is found raw and unaltered, which (hews that it has happened before they came to the place where they are now found, and that they have no growth or vegetation there, to heal or cover it ; for if there were, it would be flcinned over, as the wounds of plants and animals always are, when in a perfect, flate and living. Whenever the gloffbpetra: are taken carefully up out of the earth in Malta, the marl or earth, which ferved for their bed, is found to. contain all their minuted traces and linea- ments, like wax from a feal. This is a proof that the marl was as foft as melted wax when they were put into it, and that they were of their full fize and growth when placed there, not having grown, or had any encreafe in that place.

The apophyfes, or procefTes in the gloffopetra, are alfo a ftrong proof of their being no other than real marks teeth, fince they exactly anfwer to thofe in the teeth of recent (harks, by which every tooth is received or inferred into its neighbour in the jaw. Nay, whereas (harks teeth are mor- 1

tifed Into one another in fuch a manner, that a man may eafily tell which belongs to each fide, which He near the throat, and which near the front of the mouth ; and where- as in a fhark's mouth, the teeth on the left fide will not fit on the right, nor thofe above ferve below, but that on feeing a recent tooth, a perfon of judgment will be able to fay what part of the mouth it belonged to ; fo in the fofiile fhark's teeth, or gloffbpetra;, there is not any one which may not be referred to the particular part of the mouth of the living animal, and could have belonged to no other. Aguf- tino Scilla, de Petrifac.

SERPENTINA, in natural hiftory, a name given by later authors to the marbles which the antients called ophita, from their fpots refembling thofe of ferpents* bee the article Ophites.

SERPENTINE, (Cycl.) in the manege. A horfe is faid to have a ferpentine tongue, if it is always frilking and mov- ing, and fometimes paffing over the bit, inftead of keeping in the void (pace, called the liberty of the tongue.

SERPYLLUM, mother of thyme, in botany, the name of a genus of plants, the characters of which are thefe. The flowers and feeds are the fame with thofe of the common thyme, but the (talks are lower, lefs hard, and lefs woody. The fpecies of ferpyllum, enumerated by Mr. Tournefort, are thefe. 1. The broad-leaved hairy ferpyllwn. 2. The common large ferpyllum with purple flowers. 3. The com- mon large ferpyllum with white flowers. 4. The common lefTer ferpyllum. 5. The common leffer ferpyllum with white flowers. 6. The common fmall ferpyllum with flowers va- riegated with green and white. 7. The common fmall fer- pyllum with woolly heads. 8. The citron-fcented ferpyllum. g. The larger citron-fcented ferpyllum. 10. The narrow-leav- ed fmooth jerpyllum. 1 1 . The narrow-leaved hairy ferpyllum, 12. The loweft thyme-leaved ferpyllum. Toum. Lift. p. 107. For the medicinal virtues of mother of thyme, fee the article Thymus.

SERRA-prfis, in zoology, a name given by many authors to the pi/iris, or faw-fifh. Rondelet. p. 114. See the article Pistris.

Serra is alfo a name given by Pliny to a fpecies of the baliftes, called by the generality of writers fcolopax. . It is diftin- guifhed by Artedi by the name of the balijles with two fpines in the place of the belly fins, and one behind the anusy

SERRATA, a name given by fome of the Roman authors to the plant which the Gauls, according to Pliny, had named betonica, and which the Greeks called ceftrum pfuehrotr.,phon y and priorites. This was evidently the fame plant with our ferratula, or faw-wort. But befide this there was another plant called by this name, and which, according to Pliny, was the cbamadrys or germander of the Greeks. He fays that the chamadrys of the Greeks was a plant called by the Latins irixago, and by fome chamedrope and teucrion. He adds, that it had leaves like thofe of mint in fhape, but refem- bling thofe of the oak in their colour and divifion, and that the flower was purple. Pie adds, that the leaves were fo nicely ferrated at the edge, that it was fuppOfed men had taken the idea of a faw from them.

This author is not however to be abfolutely depended upon, and though he here exprefsly fays that this ferrata is the fame with the chamadrys of the Greeks, yet he feems to run away from this aflertion in his defcription, and to make it the fame with the other ferrata. Diofcorides fays nothing of the chamadrys, but that its leaves were fmall. And it is much more probable that the world {hould. take the idea of a faw from the leaves of the ferratula, than from thofe of this plant, they being much lefs nicely denticulated than thofe. So that thofe who have been influenced by Pliny, to fuppofe the germander and ferrata of the antients to be the fame plant, are in the wrong, though they have the coun- tenance of this fo generally reputed authentic author for it.

SERRATE flies, in natural hiffory, a name given by authors to certain flies, diftinguifbed from all the other kinds by their having a weapon, refembling a double faw, placed at the hinder part of the body : this ferves feveral fpecies of them to make holes in the branches of trees, in which they depofit their eggs ; but thefe are fome of them which do not feem to make any ufe of this curious infixument, though, they have it. See RosE-fly. .

The fly of this kind that lays its eggs on the goofcherry bufh, depofits them only on the furface of-the middle rib of the leaf; and the ofler-fly, which is one of this genus, pro- duced from a baftard caterpillar of the oiler, lays its eegs on the intermediate furface of the leaves betv/een the ribs. There appears to be no ufe made of this. curious inftrument ni the depofiting of thefe eggs, .fince. they are only hud in rows upon the leaves, and fixed to -thefji by means of a vifcous fluid which covers them. It is a very remarkable * property in the eggs of this genus of files, that they grow much larger after they arc laid. This 7 is.obiervable in the eggs of the common, rofe-fly,. which, are at firft buried- in the wood, and by their growth force out the furface into tumours of an oval figure : but in thefe of the ofier-fly it is moft beautifully feen, and the whole. growth of the ftetus in them is clearly feen, on. examining them at different times 3 of