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Show Book IV. 154 aaa ~TheAnatomy Book IV. ——— Tab. 50. Leaves, they are Small 5 in Wild Clary, a Leffler Leaf, they are very Large. In the Bodyof the Leaf, fometimes the Sides of the greater Bladders, are made upoflefler ones 5 asin Berage. ‘ 7. §. Infome Leaves, thefe Parenchymons Pil es are all drawnclofe up together, IntheFormer, they are as the Threds in the Opex-wark of Bone-Lace; in Thefe, as the fame Threds, in theCloth-mork, 8. §. The Pithy Part, in the Stalk , and almoft upto the Top of the chief Filer, in manyLeaves, is Tubular 5 even whilft theyare yet Young and Sappy: as in Sweet Chervil, Hemlock , Endive, Cichory, Lampfana, Dandelion, Burdock, Daifje, Scorzonera, and others. And fometimes the faid Pithy Part is opened into feveral little Pipes, like fo many Aer-Vefels, above $ a Foot long; as in the Common Dock and the Little Spurge, by fome called Wart-Wort. 9. §. THE Strings of the Leaf, or thofe Fibres whichare vifible to the bare Eye, are compofed of Veffels of the Two General Kinds, fc, for Sap, and for Aer. They are joyntlydiftributed throughout the Leaf: Yetnot fo, as to run meerly parallel; as in Animals, every Artery hath its Vein : but the Aer-efféls are every where Inclofed, oras it were fheathed in the Sap-Vefféls. to. §. THEIR Pofftion is various and regular, not onlyin the Body of the Leaf, asis above fhewed ; but likewife in the Stalk: of whichalfo I have given feveral Inftances in the Firf? Wook, I fhall here note, and more particularly defcribe,One or Two more. In the Stalk of a Mallow-Leaf, they ftandin Six Oblong Parcels of equal Size, and ina Réizg near the Circuit. Whereby the Stalk is {tronger, the Growth hereof, before and behind, more equal, and fo the pofture of the Leaf moreere¢t. 1. §. In Dandelyon, they ftand in Five Parcels: of which the Greater ftands a little behind the Centre of the Stalk 5 figured into a very {mall Half-Moox or Semi-Tube, whofe Diametre,: through a Glafs, is not above $th ofan Inch. The other Four, are extream {mall Cy- linders. Altogether make an Angle,twice as big as that ofa V Confonant, Whereby, although the stal& be {trong enough to fupport the younger Leaves; yet thofe which are grown longer, and fo not only by their Bulk, but their farther Extenfion from the Center of Gravity, are become more weighty ; commonlylie flat on the Ground, 12. §. In Wild Clary, they ftand alfo in Five Parcels, the Greater {tands not behind, but before the Center s making an Arch, whofe Chord in a Glas, isabove : an Inch long; and belongeth toa Circle, whofe Diameter is an Inch and half. The other Four,are fmall Cylinders, alfo different from thofe in Dandelion; the two bigger, there {tanding hindmoft; but here, the two Lefs, and the two Bigger, within the two round Ridges of the Stalk. 13. §. From henceit is, that the Leaves of this Plant have not on- ly a Prone or Horizontal Pofture,but alfo make that Forceable Preffure on the Ground, which can by no means be imputed to their Weight. For the Great Arched- Fibre {tanding before the Cetre of the Stalk, and thetwo Longer Roundones being uppermoft, in the Ridges of the Stalk; they put on the upper parts thereof to a more full and for- ward Growth, andfo to bow the Leaf back-ward. And the Fibrous Arch being, though broad, yet almoft flat, doth hereby the more eafily yield to that Motion, 14, 5: 14, §. ofLeaver. In Borage, and Moth-Mullen, they ftand alfo in Five Par- eels. Inthe former, thelargeft maketh {till a more bulky Arch, than Tab. 49. that of Clary; being thicker, as broad, and of a lefler Circle or more bowed. But in MuZein, it maketh almoft an entire Oval. 15. §. By means ofthis Figuration, a fufficient number of Feffels for fuch large Leaves, are not only more conveniently Diftributed into them ; but alfo ftand more fafely in the stalk, For were the Arch contracted into a Jolid Cylinder, it could notfo prefently be refolved into {mall Fibers. And wereit laid into a flat Plate, orftraight out, either the Figure of the stalk, and fo of the Leaf, mutt be altered ; or elfe, the two ends of the P/ate, would come too near the Circumference of the Stalk , and fobe moreliable to the Inpreffions of the Weather : as may be obferved in cutting the Stalf tranfverfly, and by the Figures. 16. §. IN the Body of the Leaf, befides the Pofttions of the Fibrous Strings or Thredss above expefled, there is one Thred, bigger or lefs, whichin all Plants, runs round the Edge of the Leaf, and hemsin all the ref{t; but can hardly be well obferved in any, without ftripping offthe Skin of the Leaf. Whenthe Fibres of the Leaf, are bigger,orlefs tender, £44 50. asin Holly , the Skin and the Pulp are fometimes found either rotted off, or eaten away with Infecfs; whereby, both the faid furrounding Fiber, and the reft, are all very fairly vifible. 17. §. THE Vefelsfeem tobe continu’d, in the Leaf, by being Ramified out of Greater into Lefs, as eins or Arteries are in Animals. But if the Skin and Pulp ofthe Leaf, as fuppofe a Borage-Leaf be taken off, and the Vefels laid bare 5 by the help of a good Gia/s, it will ap- pear 3 That theyareall ofthe fame Size, every where in the Leaf; Tab. 50. and alfo continued throughout thefame, all {everal and dilting Pipes one from another, as the Threds ina Shein of Silk, And that therefore the Diftribution ofthe Threds which the Veféls compofe, is not the Ramifying of Greater Pipes into Le but the dividing a greaterClufter of Pipes, into feveral leffer Clufters, till at laft they cometo befingle; as in the Diftribution of the Nerves. 18. §. The Vefels feem alfo to be Inofeulated, not only fide to fide, but the ends of fome into the Sides of others. But neitheris this everreally done : the lefler Threds, being only fo far diduéted, as Tab. 50: fometimes to ftand at Right- Angles with the greater. So that they are Inofculated only End to End or Mouth to Mouth, after they are come at laft to their final diftribution. 19. §. The Aer-Veffels, are not only, as is faid, Exiftent in the Leaves ofall Plants ; but are herein alfo difcoverable without the help of Glafés: For upon breaking the stalk or chief Fibers of a Leaf ; the likenets of a fine Wooly Subftance, or rather of curious fmall Cobwebs, may befeen to hang at both the broken Ends. This is taken notice of, only in fome few Plants, asin Scabious, where it is more vifible. But may alfo be feen moreorlef, in moft other Plants, if the Leaves be ve- 140.51, & ry tenderly broken: as I have noted near twenty years fince; and 52+ thence conjectur'd them a Sort of Veffel common to Plants. Nowthis fine Wool, is really a Skeiv of Aer-Vefféls, or rather of the Fibers ofthe Aer-Vefféls, unroaved from their Spiral Pofition, and {fo drawn out in Length. As they appear thus unroaved and drawn out at Length, both to the bare Bye, and through a good Microfcope, I have reprefented in two Exemples, the one a Scabious Leaf, the other that ofa Fine. Ce 3 20. $. |