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the vefTels of plant ,-, othervtife than by thefe frits. Mem Acad. Par. 1^93.

It is very obfervable, in the courfe of thefe experiments, that the crefs, tho' planted in an earth containing fait petre, which is well known to be an acid fait, yet yielded, on the analyfis, alcaline principles- and not the Ieaft mark of an acid in any part of the proceiTcs, and this juft in the fame manner as if it had grown upon an earth impregnated with dung ; and that the fennel, whether growing on the nitrous earth, or on the infipid. afforded a Urge quantity of acid in all its principles, not excepting even its fixed fait, which was very little of the alkali ; and by the mixture of t!ie acid of the plant was con- verted almoft into the nauire of a neutral fait. Hence it ap- pears that a fait, tho' acid in itfelf when abforhed into the veflels of an alkaline plant, fuch as the crefs, ceafes to he any lunger an acid ; and that a plant naturally acid, whether it grow in an earth impregnated with an acid fait, or wholly diverted of falts, yet it retains its acid nature, and "ives proof of it in all its principles on an .uidlvfis ; whence it is very reasonable to conclude, that the fahs found in plants are made what they are in thofe pi.nis; and that the falts of the earth, in which the plant grows, be they of what nature they will, will change that nature in the veifels of the plant, according to the diverfity of its organs, and of the different fermenta- tions they undergo in the courfe of their alteration there. The weights above mentioned are French, the word r ros being translated drachm, tho' really exceeding it by twelve grains. See Wught, Cxi.

TraJjcrv of Plants See the article Tracheae of plants.

T'tnij ortntion of 'Plants. See Transpor/i atjon of plants.

Plani $in Amber I he cabinets of the curious afford numerous initances of fmall animals, fuch as flies, beetles, and the like, buried in amber ; bin the parts of plants are more rarely found thus preferved ; yet we are not without infiances that the fame ! accident may happen to them. Hie learned Hartman men-' tions a piece of amber in his own pofleffion, in which there were preferved fome leaves of the common alga, and another 1 in which a feed of the common lime-tree, with part of its pe- 1 dicle, and others in which the capfule with its feeds and pe- ' dicle were preferved ; the pedicle {landing out at the end of! the piece of amber.

Some have given accounts of whole pinnated leaves of plants thus preferved, and the moffes are fo common, that there is : no doubt of the reality of their being naturally buried there. 1 'I hey are generally found only in fingle leaves and fmall frag- ments, but fometimes in whole branches; in which cafe am- ! bet can fhew no greater beauty. Pieces of ftraws, fticks, and the barks of trees are often found in it alfo ; but the greater part of thefe, when ftriflly examined, are found to be frag- ments of foffiie wood, or of the matter called by Hartman the matrix of amber ; which is a fibrofe fubftance, and much of the appearance of wood, but is really only a bituminous earth. Thefe all mult have been received into the amber in the fame manner that the infects were; that is, while the am- ber was yet moift or foft. 7'hefc things falling into its way might bury themfelves in it, and then muft be preferved in it in the hardened fiate. See Succinum.

Foffiie Plants. Many fpecies of tender and herbaceous plants are found at this day, in great abundance, buried at confider- able depths in the earth, and converted, as it were, into the nature of the matter they he among ; foffiie wood is often found very little altered, and often impregnated with fub- ftances of almoft all the different foffiie kind', and lodged in all the feveral ftrata, fometimes firmly embedded in hard matter, fometimes loofe : but this is by no means the cafe with the tenderer and more delicate ful>je£ts of the vecetabli woria. Thefe are ufually immerfed either in a blackilh (lacy fubftance, found lying over the ftrata of coal, or elfe in loofe nodu'es of ferrugineous matter of a pebble-like form, and they are always altered into the nature of the fubftance they lie among; what we meet with of thefe are principally of the fern kind ; and what is very fingular, tho' a very cer- tain truth, is, that thefe are principally the ferns of Ameri- can growth, not thofe of our own climate. The moft frequent foffiie p'ants are the polypody, fpleenworr, ofmund, trichomanes, and the feveral larger and fmaller ferns ; but befide thefe there are alfo found pieces of the equifetums, or horfe-tails, and joints of the ftellated plants, as the clivers, madder, and the like ; and thefe have been too often miftaken for flowers; fometimes there are alfo found compleat graffes, or parts of them, as alfo reeds and other water plants ; fome- times the ears of corn, and not unfrequcntly the twigs or hark, and impreffions of the bark, and fruit of the pine or fir kind, which have been, from their fcaly appearanc-, mif- taken for the (kins of fifties ; and fometimes, but that very rarely, we meet with moffes and tea-plants. Many of the ferns not unfr quently found, are of very fin- gular kinds, and fome fpecies yet an known to us j and the leaves of fome appear fet at regular diftances, with round protuberances and cavities. The flones which contain thefe plants 'fplit readily, and are often fonnd to contain, on one fide, the impreffion of the plant; and on the other the pro- minent plant itfelf; and befide all that have been mentioned, there have been frequently fuppofed to be found with us ears Suppl. Vt-L. II.

PLA

of common wheat, and bf the maiz or Indian corn ; the

branches of the firs, and the other the thicker boushs of Va nous fpecies of that and of the pine kind, with their leaves fallen oft; fuch branches in fuch a date cannot but afford many irregular tubercles and papillae, and in fome fpecies, fuch as are more regularly difpofed.

Thefe are the kinds moft obvious in England ; and thefe are cither immerfed in the (laty ftone which constitutes whole ftrata, or m flatted nodules, dually of about three inches broad, winch readily fplit into two 'pieces on being (truck. j J, "? "',, common "' Ke "ton coal-pits, near Ncwcaftle, ami the foreft of Dean, in Gloucefterfhire; but are more or leis found about almoit all our coal-pits, and many of our iron mines. See 7 ab. of Mils, Clafj 6. Tho' thefe feem the only fpecies of plants found with us, yet in Germany there are many others, and thofe found in dif- ferent fubttances. A whitifh (tone, a little harder than chalk fre- quently contains them : they are found alfo often in a <rrey flaty (tone, of a firmer texture, not unfrequently in a blackifn one and at times in many others : nor are the bodies themfelves lels various here than the matter in which they are contained • the leaves of trcesare foundin great abundance, amone which thole of the willow, poplar, whitethorn, and pear-trees, are the moft common ; fmall branches of box, leafs of the olive- tree, and (talks of garden thyme, are alfo found there: and fometimes ears of the various fpecies of corn, and the larger as well as the fmaller moffes in great abundance Thefe feem the tender vegetables, or herbaceous Hants, cer- tainly found thus immerfed in hard ftone, and buried at <rreat depths in the earth ; others of many kinds there are alfo named by authors, but as in bodies fo imperfect, errors are eafily fallen into, thefe feem all that can be afcertained be- yond mere conjefture. Hilts Hid. of Foff. p. 640

fe-PLANT Seethe article Icf.

Plant-™/, a term ufed by Dr. Grew to exprefs the radicle in feeds : he by this name diftinguilhes it from what he calls the fcm.nal root ; which is a very different fubftance diftributed •throughout the parenchyma of the feed, but wholly different from it, and preying upon it as the plant-rast does upon the

DrT^»r"x, S r- Anatofl " lants - Seeth "rticle Seminal-™*.

PLAN I ALr.Ni.LLA, in botany, a name given by Dillenius to a genus of plants fince called by Linnaeus Bmqfella. Dil- lon See the article Limosella.

PLANTaGO, plantain, in botany, the name of a genus of plants, the characters of which are thefe : The flower confifts of one leaf, and is wide, expanded at the opening, and ufual- ly divided into four fegments ; from the bottom of this flower nfes a piftil furrounded with (lamina of confiderable length : the piftil becomes afterwards an oval or conic feed-vefle! - which when ripe feparates tranfverfely into two pieces, and is divided by an intermediate fcptum into two cells, filled with oblong feeds.

The fpecies of plantain, enumerated by Mr. Tournefort, are thefe: 1. The fmooth broad-leaved plantain. 2. The broad- leaved plantain, with finuated leaves. 3. The broatl-ieaved plantain, with blood coloured leaves. 4. The broad-leaved hoary plantain. 5. The broad-leaved hoary plantain, with a white fpike 6. The broad-leaved rofe plantain, with an expanded flower. 7. The broad-leaved rofe plantain, with flowers difpofed in tufts. 8. The broad-leaved plantain, with a bufhy panicle. 9. The broad-leaved hoary plantain, with various (pikes. 10. The fmaller broad-leaved fmooth ska- tes. 1 1 . The fmaller broad-leaved hoary plantain 1 ->. The hairy or woolly plantain. ' 13. The great narrow-leaved plan- tain. 14. The fmall proliferous narrow-leaved plantain with fohaceous tops to the (talks. 1 5. The common narrow- leaved^ proliferous plantain. 16. The narrow-leaved filvery plantain. 1 7. The narrow-leaved lerntei plantain. 18. The fhrubby narrow-leaved plantain. 19. The great broad-leaved hoary plantain, with three ribs to each leaf. 20. The lefl'er narrow-leaved -plantain. 21. The hairy bulbofe rooted plan* tain. 22. The narrow-leaved plantain, with tufts like the lagopus. 23. The narroweft-leaved three ribbed plantain.

24. I he alpine plantain, with long, narrow and blackilh leaves.

25. r he three-ribbed mountain-/>.fcte's. 26. The narrow- leaved and white Spanifli plantain. 27. The narrow-leaved white French plantain. 28. The great narrow-leaved fea- plantain, called by fome the fea armopus. 29. The lefl'er narrow-leaved kn-plantain. 30. 1 he fmalleft kz-plantain with rigid grall'y leaves. 3 1 . The greater graffy-leaved flan' tain. 32. The fmaller grafi'y-leaved plantain. 33, The fmalleft narrow leaved plantain, with heads like the hare's foot 34. The one-flowered graffy-leaved mar(h-/;kiite's. 35, The hairy leu-plantain of Portugal, with a very long fpike. 36. The hairy kt-plantain of Portugal, with a (hort fpike. Thefe are properly plantains ; but the large plants commonly called by authors water plantains, are fpecies of ranunculus. Tmrit. Inft, p. 127. See Ranunculus.

PLANTAGO, in the Linnseari fyftem of botany, is made the name of a large genus of plants, taking in, befide the feveral fpecies of plantains, ufually (beaded, the pfyllium, or fleawort, the coronopus or bucklhorn, and the gramen junceum, or ruih-grafs.

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