The anatomy of plants

EXT WITHIN the Skin lieth the Barque. ’Tis sometimes Yellow, as in Dock; Red, in Bistort; but usually, and in Seed-Roots, I think, always White. It is derived from the Seed it self; being but the extension or prolongation of the Parenchyma of the Radicle; One of the three Organical Parts of the Seed, described in the First Chapter of the First Book.

2. § It is variously Sized; sometimes very Thin, as in Jerusalem Artichoke, Goats-beard, and in most Trees; where it also retains the Name of a Barque or Rind. Sometimes ’tis more Thick, and maketh up the far greatest portion of the Root, as in the String-Roots of Asparagus, in Dandelion, and others. The thinnest and the thickest are all analogous, and obtain the same general Uses. The degrees of its Size, amongst all Roots, may be well reckoned about Twenty, and seen in the following examples, Tab. 7, 8, 9. sc. Beet, Dropwort, Jerusalem Artichoke, Orpine, Valerian, Goats-beard, Nettle, Brownwort, Columbine, Celandine, Asparagus, Horse-Radish, Peony, Bryony, Eryngo, Borage, Lovage, Dandelion, Parsnep, Carrot, &c. In the Root of Beet, scarce exceeding a good thick Skin: but in a Carrot, half the Semidiameter of the Root, or above half an Inch over in some places: and that of Dandelion, sometimes, in proportion with the woody Part, twice as thick: the rest of Several intermediate Degrees: And to most Roots, this is common, To have their Barque proportionably thicker, at the bottome than at the top.

3. §. IT IS Compounded of two Bodies. The one Parenchymous; Continuous throughout; yet somewhat Pliable without a solution of its Continuity. Exceeding Porous; as appeareth from its so much shrinking up, in drying. The Pores hereof are extended much alike both by the length and bredth of the Root; therefore it shrinketh up, by both those Dimensions, more equally. And they are very Dilative; as is also manifest from its restorableness to its former bulk again, upon its infusion in Water: that is to say, It is a most curious and exquisitely fine wrought Sponge. Thus much the Eye and Reason may discover.

4. §. The Microscope confirms the truth hereof, and more precisely shews, That these Pores are all, in a manner, Spherical, in most Plants; and this Part, an Infinite Mass of little Cells or Bladders. The sides of none of them, are Visibly pervious from one into another; but each is bounded within it self. Tab. 10, & sequent. So that the Parenchyma of the Barque, is much the same thing, as to its Conformation, which the Froth of Beer or Eggs is, as a fluid, or a piece of fine Manchet, as a fixed Body. The Sides also of these Bladders are as transparent, as those of Water; or the Bodies of some Insects.

5. §. But their Size is usually much smaller; and their Posture more Regular than those in Bread or Water. In all Roots they are so small, as scarcely, without the Microscope, to be discerned: yet are they of different Size, both in the same, and in divers Roots; the varieties whereof, amongst all Roots, may be reduced to about Ten or Twelve according to the Standard, in Tab. 11. Tab. 13, 14. Some of those in Dandelion, being of the Smallest; and in Bugloss, of the Greatest. They are posited, for the most part, at an Equal Height; and piled evenly one over another: So that, oftentimes, they visibly run in Ranks or trains, both by the length and breadth of the Roots, as in the Root of Bugloss, or of Dandelion, split through the middle, may be seen. Although they are usually Spherical, yet sometimes, and in some places, they are more oblonge, Tab. 14. as in the outward part of the Barque of Bugloss. These Bladders, are sometimes best seen, after the Root, being cut traverse, hath layn by awhile, to dry.

6. §. They are the Receptacles of Liquor; which is ever Lucid; and I think, always more Thin or Watery. They are, in all Seed-Roots, filled herewith; and usually, in those also which are well grown, as of Borage, Radish, &c.

7. §. THIS Parenchymous Part, in many Roots, is of one Uniform Contexture; as in Asparagus, Hors-Radish, Peony, Potato, and others. In many others, it is, as it were, of a Diversified Woof; the Bladders being, though every where Regular, yet either in Shape, Size, or Situation, different in some Parts hereof, from what they are, in other intermediate ones. For these Parts, are like so many White Rays, streaming, by the Diameter of the Root, from the inward Edge toward the Circumference of the Barque; as in Lovage, Melilot, Parsnep, &c. cut transversly, is apparent. Tab. 8, 9. They are, though not in direct Lines, continued also by the length of the Root; so that they are, as it were, so many Membrances, by which the other Parts of the Barque, are disterminated.

8. §. The Continuation of these Diametral Rays, or Portions, is divers: sometimes, but half through the Barque, or somewhat more, or less, as in Melilot. Tab. 9. And it is probable, that to the Roots of all or most Trefoyls, and also of the Leguminous Kind, this is proper, To have their Diametral Rays come short of the Circumference. Tab. 8. Sometimes, they run quite through to the very Skin, as in Lovage. And I think, in the Roots of all Umbelliferous Plants: In which therefore, the Skin seems to have a closer Communion with the Diametral Rays, and to be originated especially therefrom. They usually stand at an Equal Distance in the same Root: But with respect to divers Roots, their Distance varies;Tab. 7, 8. so less, in Parsnep, greater in Bugloss. They are commonly Rectilinear, as in Lovage; Tab. 8. but sometimes winding to and fro, as in a Carrot.

9. §. They are not always of one Size: in a Carrot near the Inner Edge of the Barque, exceeding Slender, and scarcely discernable; in others, Thicker, as in the Three greater ones of Melilot, and in common Chervil. Tab. 8, 9. Both by their Distance, and Size, they are also less or more Numerous; some, only as they are nearer; some, as smaller; others, as both. And ’tis proper, I think, to the Intybous kind, either to have none, or but a few. Sometimes they are of the same Thickness quite, through the Barque from edge to edge, as in Marsh-Mallow. Tab. 7. And sometimes are considerably spread or dilated as they aproach the Skin, wherewith they are joyned, and whereinto they more visibly run, as in Parsley, or the smaller part of the Root of Lovage. Tab. 8. And in some Roots, as of Scorzonera, at some times of the year, when less succulent, almost the whole Parenchyma seems to be of the Nature of the Diametral Rays, in other Roots. The Bladders of these Diametral Portions, are sometimes, greater than those of the other Parenchymous Parts, as in Parsley; and I think sometimes less. Yet as there, so here, variously sized; to about six or eight Degrees; and those of Parsley about the third, fourth, and fifth. Their Figure is Sometimes more oblong; and their direction or respect more towards the Center of the Root.

11. §. As the other Parenchymous Parts of the Barque, are the Receptacles of Liquor; so these, (where they are) of Aer. This is argued, From their being more White, and not Transparent, as such Roots and Parts use to be, which are more copiously and equally filled up with Liquor: as the Pith of Elder, which, in the old Stalks, is White; was once, and by being well soaked, will become, again Transparent. And from their being more dry and voyd of Liquor; whereupon their Bladders, which cannot be Vacuities, must be filled with more or less Aer, mixed with the Sap or the Vaporous parts thereof. This is more observable in those Diametral Portions, which terminate upon, and run into the Skin.

12. §. THE BARQUE is not only of a divers Woof, but as is said, of a Compounded Substance; there being a certain number of Lignous Vessels, fewer or more, in some place or other, mixed with the Parenchymous Part above described; and some way or other, are demonstrable in all Roots. As by the Toughness of the Barque, when pulled by the length. By the visible Continuation of the said Vessels through the length of the Barque, in the resemblance of small Threds. Tab. 6. And by the rising up of the Sap in the traverse cut of the Root, in such places of the Barque, where these Threds terminate: as the existence of the same Vessels in the Skin, was proved in the Precedent Chapter.

13. §. These Tubulary Threds, run not through the Barque in direct lines; but are frequently Braced together in the form of Net-Work; The Parenchymous Parts every where filling up the spaces betwixt the Braced Threds; Tab. 6. as in Burnet, Scorzonera, &c. the Barque being paired or striped off, is apparent.

14. §. They seem, at first, where they are Braced, to be Inosculated; so as to be pervious one into another. But a more accurate view, especially assisted by a Microscope, discovers the contrary. Neither are they woun’d any way one about another, as Threds are in a Rope: nor Implicated, as in ravled Yarn, or the Knots of a Net: but only contiguous or simply Tangent, as the several Chords in the Braces of a Drum: being thus joyned together by the Parenchymous Parts, as in speaking of the Pith, will be understood how. Yet do not always the same Threds belong and keep entire to one Brace; but are frequently parted into lesser Threds; which are transposed from Brace to Brace. Nor do they always, in whole or in part, presently after their contingence, mutually fall off again; but, oftentimes, run along collaterally joyned together for some space.

Tab. 6. 15. §. These Braces are of various number in divers Roots; more frequent in Jerusalem Artichoke, less in Scorzonera, more rare in Cumfry. The Threds likewise are variously Divaricated; sometimes more, where the Braces are frequent, as in Jerusalem Artichoke; and sometimes less, where the Braces are rare, as in Scorzonera, Dandelion: And in all Roots, more frequent towards the Inner Verge of the Bark.

16. §. By what is said, it is partly implied, That these Threds, are not Single Vessels; but a Cluster of them, Twenty, Thirty, or more or fewer of them together. Yet as the Threds are not Inosculated in the Braces; so neither are the Vessels, in the Threds. Nor yet Twisted; but only stand collateral together; as the several Single Threds of the Silkworm, do in Sleave-Silk. Neither are these Vessels pyramidal, so far as the Glass will discover; or, from probable Reason, may be conjectured. Nor Ramified, so as to be successively propagated one from another, after the manner of the Veins in Animals: but Cylindrical, and Distinctly continued, throughout the length of the Root; as the several Fibres in a Tendon or Nerve.

17. §. THESE VESSELS are either themselves of divers kinds, or serve, at least, to constitute divers Kinds, in divers Roots: of the different Natures whereof, although there may be other ways whereby to judge; yet so far as by Inspection, we may do it, chiefly, by the Diversity of those Liquors, which they severally contain. Sometimes they yield a Lympha; and that Thin, as they do in a Parsnep; especially those that make a Ring, at the inward extremity of the Bark. See the Root it self. That this Clear Sap ascendeth only from these Vessels, is certain. Because no Liquor will do the like, from any Parenchymous Part, as Chap. 2. hath been said. And because it is of a different nature from the Sap contained in the Bladders of the Parenchyma; although of the same Colour, yet sensibly more Sweet.

18. §. Sometimes they yield a Thick and Mucilaginous Lympha, as in Cumfry, as appeareth by its tenacity. From the Mucilaginous Content of these Vessels it is, I suppose, that the Sap contained in the Bladders is rendred of the like nature, so far as it approaches hereto, which sometimes is more, as in Marsh-mallow; and sometimes but little as in Borage: For in pressing out the Liquor of this Plant, and then heating it over an indifferent fire; the far greater part hereof remaineth thin; only some certain strings and little bits of a gellied substance are mixed herewith; which as it seems, were originally the proper Liquor of these Muciducts.

19. §. Oftentimes these Succiferous Vessels yield a Milky or White Sap; and sometimes Yellow, and of other colours as in Sonchus,and most Cichoraceous Plants; in Angelica, and most Umbelliferous; in Burdock, and divers Thistles, to which that is ’akin: in Scorzonera, Common Bells, and many other Plants, not commonly taken notice of to be milky. The Milky Saps of all which, although they differ in Colour, Thickness, and other Qualities; yet agree, in being more Oyly than any of the Lymphous Saps. It being the mixture of the Oyly parts with some other Limpid Liquor, but of a different Nature, which causeth them to be of a Milky, or other Opacous Colour, in the same manner as common Oyl, and a strong Liquamen of Tartar, shaked in a Bottle together, presently mix into a White Liquor. And although they will, for the greatest part, separate again; yet some of their parts, without any Boiling, or so much as the least Digestion with Heat, by Agitation only, or standing together for some time, incorporate in the form of a Thin Milky-Sope, which will also dissolve in Water. I suppose, therefore, That it is the Volatile Salt, chiefly, of these Plants, which being mixed with their Oyl, renders this Liquor of a White or other Opacous Colour.

21. §. All Gums and Balsams are likewise to be reputed the proper Contents of these Vessels: for These and Milks, are very near akin. So the Milk of Fenil, upon standing, turns to a Clear Balsam; of Scorzonera, Dandelion, and others, to a Gum. In the dryed Root of Angelica, &c. being split, the Milk, according to the Continuation of these Vessels, appeareth, as Blood clodders in the Veins, condensed to an hard and shining Rosin. Tab. 9. And the Root of Helenium cut transversely, presently yields a curious Balsame of a Citrine Colour, and sometimes of the Colour of Balsame of Sulphur. I call it a Balsame; because it will not dissolve in Water. Yet not a Terebinth; because, nothing near so viscid or tenaceous as that is. But the Root of Common Wormwood, bleeds, from large Vessels, a true Terebinth, Tab. 10. E. or a Balsame with all the defining properties of a Terebinth; although that word be commonly used only for the Liquors of some Trees.

22. §. There is yet another kind of Sap-Vessels, which may be called Vapour-Vessels; as in Docks, at least some of them. For by the Sap-Vessels it is, that the Barques of Roots do Bleed. Of which, some Bleed quick and plentifully, as the Umbelliferous and the Cichoraceous Kinds. Some, very slowly and scarce visibly, as all or most Trefoyls, and of the Leguminous Kind. And some seem not to Bleed, as the Dock. Yet that this Root, hath also Vessels distinct from those that carry Aer; doth partly appear, from the different Colour they produce where they stand; as will better be understood anon, in speaking of the Causes of the Colours of Roots. As also from the Toughness of the Barque, in pulling it by the length; neither the Parenchyma, nor the Aer-Vessels, being of themselves Tough. But because the Succus or Sap they carry, seems to be a kind of Dewy Vapour, therefore, they may not improperly be called Roriferous or Vapour-Vessels.

23. §. THE Sap-Vessels, are not only of divers Kinds, in divers Roots, but in the same. Whether in all, I doubt: but in some it is certain they are: Tab. 9. For if you cut a Fenil-Root traverse, both Milk and Limpid Sap, will presently ascend, and, upon accurate inspection, appear thereupon distinctly. So the Roots, both of Trachelium and Enula, Bleed both a Lympha, and a Citrine Balsame: and Wormwood, both a Lympha, and a Terebinth, at the same time. So also the Root of Dandelion being cut in November, seems to bleed both a Milk and a Lympha; the latter being drowned by the former at another time when it is more copious. Whether all Roots have Lymphæducts, is doubtful; but ’tis most probable, that they have, more or fewer; standing, for the most part, in a Ring, at the Inner Verge of the Barque: the Sap whereof, I suppose, is so far of common Nature in all Roots, as to be Clear, and less Oily.

24. §. THE Quantity of these Vessels is very different: In Borage, Peony, Bistort, but few; in Asparagus, fewer: in Parsnep, Celandine, many; in Fenil, Marsh-mallow, many more: and betwixt these extreams, there are many Degrees, Tab. 7, 8, 9. as by comparing the Roots of Horse-Radish, Turnep, Briony, Skirrets, Parsley, Goats-Beard, and as many more as you please, may be seen. Amongst the several Sorts of Docks, they seem in Patience, to be the fewest; in Red-Dock, the most numerous. There are two ways of judging of their Number; Either as their Extremeties are visible upon the traverse cut of the Barque; or as the Barque is diversly Brittle or Tough; being so, from the various Number of these Vessels therein, as in the Second Chapter hath been said.

25. §. The Quantity of the ascending Sap, is a doubtful argument, whether of the Number, or Size of these Vessels. For it is common to most Milky-Roots, for the Milk to ascend more copiously: yet in some of them, the Vessels seem, in proportion with the Parenchymous Part, not to be so numerous, as in some other Roots, where the ascending Sap is less; as by comparing the Lacteals of Dandelion, and the Lymphæducts of Fenil together, may appear: so that it should seem, that the bore of the Lacteal Vessels, is greater than that of the Lymphæducts.

26. §. THE Situation of these Vessels, as they appear, even to the naked Eye, in the transverse Section, is Various and Elegant. Sometimes they are posited only at the Inner Edg of the Barque, where they make a Ring, as in Asparagus. Tab. 7, 8, 9, & 10. In which place and position, they stand in most, if not in all, Roots, how variouslly soever they are posited also otherwise. The Common Crow-Foot with numerous Roots, hath a Ring of Sap-Vessels next the Skin. So the Barque of Monks-Hood, is encompassed with a transparent Ring of Sap-Vessels. The Ring is either more Entire, as in Eryngo, Brown-Wort, Valerian, Hop, Madder, &c. Or it is a Prick’d Ring, as in Buttyr-Bur. Sometimes they are chiefly postur’d in a Prick-Ring, towards the outward part of the Barque, as in Peony: and some Roots are pricked all over the Barque, as of Melilot. In others, they stand not so much in Pricks, as Portions or Colums, as in Cumfry.

27. §. In others, again, they all stand in more continued Lines, either Rays or Diametral, as in Borage; or Peripherial, as in Celandine. The Vascular Rays are not equally extended in all Roots: in Parsnep, towards the Circumference of the Barque; Tab. 7, 8, 9. in Bugloss, about half way. In all Docks, and Sorrels, the Rays are extended through about ¾ of the thickness of the Barque, towards the Circumference, whereabout, divers of them are always arched in, two and two together. In all or many Trefoyls, and of the Leguminous Kind, they are extended through no more than ⅓ᵈ of the Barque. In the Umbelliferous, they are Ralled in betwixt the Diametral Portions of the Parenchyma. In Borage, the Rays are more Continuous; in a Carrot, more Pricked. Here also the Pricks stand in Even Lines; in Lovage, they are Divaricated. Of which, and those of some other Roots, it is also Observable, That they are not all meer Pricks, but most of them small, yet real Circles; Tab. 8. which, after the Milk hath been frequently licked off, and ceaseth to ascend, are visible, even without a Glass. And note, that in observing all Milk-Vessels, the Milk is to be taken off, not with the Finger but the Tongue; so often, till it riseth no more, or but little. And some Roots may also be soaked in Water; whereby the Position of the Milk-Vessels, will be visible by the darker Colour of the Barque, where they stand.

28. §. The Rays sometimes, run more Parallel, and keep several, as in Monkshood; and sometimes, towards the Circumference of the Barque, they are occurrent; Tab. 7, 8, 9. as not only in Docks, but other Plants: In Eryngo, in a termination more Circular; and in Bryony, angular, or in the form of a Glory, as also in Horsradish, through a Microscope. Tab. 15. The Peripherial Lines are in some, more entire Circles, as in Dandelion; in others, made up of shorter Chords, as in Potato, Cumfry, and the smaller part of the Root of Monks-hood. In some, the Pricks are so exceeding small, and stand so close, that, to the bare eye, they seem to be continuous Rings, which yet, through the Microscope, appear distinct, as in Marsh-mallow and Liquirish. Tab. 12.

29. §. Sometimes Columns and Chords are compounded, as in Burnet; Pricks and Chords, in Potato; Rays and Rings, in Monkshood; where the Ring is Single. In Fenil, there is a double or treble order both of Rays and Rings, the Lymphæducts standing in Rays and the Lacteals in Rings. And in Marsh-mallow, the Vessels are so posited as to make both those kinds of Lines at once.

30. §. In Celandine, they seem all, to the bare eye, to stand in numerous Rings lying even one within another. As also in Dandelion; in which yet, being viewed through a Microscope, Tab. 13. there is an appearance of very many small Rays; which streaming from the Inner Verge of the Barque, cross three or four of the smaller Rings, and are there terminated. Whence it should seem that Lymphatick Rays and Milky Rings, are in that Root, so far mixed together. Only the Lympha, being confounded with the Milk, cannot be discerned. And where the Milky-Vessels are evacuated, or at such Seasons, wherein they are less full, divers Milky Roots will yield a clear Liquor at the Inner Verge of the Barque, where, at other times, they seem to yield only Milk. And this is the Description of the Barque.