mous one with feveral fmall Knobs refembling Grains of Corn; as in the white Saxifrage, &c. (8.) A Tap-Root, or a tuberofe one extended in Length in Form of a Tap or Faucet; as thofe of Carrots, Parfnips, &c.

Tap-Root.

THE STALK or STEM of Plants and Ve- The Stalk of a getables is the most principal or fubftantial Part, Plant. which arifeth out of the Root, and fuftains the Leaves, &c. and is towards the upper Part generally divided into various Limbs or Branches. Scarce any thing admits more Variety than the Size, Figure, Colour, and Texture of this Part. I fhall obferve only the following Particulars. (1.) That several Stalks of Plants have Joints Their Joints or Knots, the Ufes of which are faid to be the or Knots. Strengthening the Stem, and finer Growth; for

the Juices, being filtrated thro' thefe Knots, are tranfmitted more fine and good to the upper Parts, and to the Fruit. (2.) The Stalks of ma- Their Cavity. ny Plants are tubulous or hollow; hence a great Quantity of Air filling this Hollow, conduces to the more expeditious ripening the Fruit or Seed; and alfo by drying up the Sap, and fhrinking the Veffels, determines the Life of the Plant to a fhort Period: Hence moit annual Trunks are obferv'd to be hollow. (3.) The Pith is the Their Pith. middle Part of the Stalk, confifting of an immenfe Number of little Veficles, which feem deftin'd to filtrate and elaborate the finer Juices neceffary for the Leaves, Flowers, and Fruit; according as the Medullary Subftance of the Brain fecretes the fine Fluid call'd the Animal Spirits. (4.) The Wood, or lignous Part of the Stalk and The Wood. Trunks of Trees: This confifts of flender capillary Tubes, running parallel to each other from the Root up the Trunk; these receive a fine Juice, which diftending their cellular Texture caufes the Trunk to grow and increase yearly in

Circum

Veffels.

Circumference; and thofe annular Increments are visible on a tranfverfe Section of the Trunk, and fhew its Age. (5.) Through all the woody or lignous Part appears the Syftem of Air-Veffels or Trachea, eafily difcernible by the Microfcope; Bark or Rind, but of thefe already enough. (6.) The Bark or Rind, which makes the common Integument of the Trunk or Stem of Vegetables. This Part confifts of a fine Skin or Cuticle, under which lies the Cortex or true Skin, which we call the Bark: The Subftance whereof is made up of small Bladders, interwoven with fine foft and flexible Fibres, which makes a kind of reticular Texture, the longitudinal Fibres of which grow hard by degrees, become woody, and leaving the Nature of Bark, join the lignous Substance in Form of Ringlets, making the fappy Part thereof. But others are of a different Mind concerning the Nature and Ufe of the Bark, the Theory of which is not yet fettled.

Of the Leaves of Plants.

Their Stru-
Eture.

THE LEAVES of a Plant are the next Part to be confider'd. They are properly the most extreme Part of a Branch, and the Ornament of the Twigs; they confift of various Fibres minutely ramified, the Interftices whereof are fill'd with a parenchymous Substance. The Fibres are analogous to Arteries and Veins, which bring and return the Sap after it is fubtilized and refined in paffing the veficular Texture of the Parenchyma. Tranfpiration. Befides this, the Bufinefs of Tranfpiration is carried on in the Leaves, for by their excretory Vef

fels they exude or fweat forth what is fuperfluous

in the Circulation of the nutritious Moisture. Refpiration. That Leaves are the Organ of vegetable Refpiration has been already obferv'd; and that they not only expire, but alfo infpire or draw in the Air thro' their numerous Pores, is pretty reasonable to fuppofe; and that with the Air, they imbibe a Part

a Part of their Nourishment likewise. Lastly, the Leaves of Trees ferve for Protection to the Gems or Buds, and the Flowers and Fruits, which are hereby fcreen'd in a good measure from the Injuries of Wind and Weather. These are the principal of the many Ufes affign'd to the Leaves

of Plants. The Size, Form, Colour and Superfi- The Kinds of cies of Leaves are fo various, that it were end- Leaves. lefs to recount them all. I fhall only observe, that a Leaf is faid to be Simple, which is not di- Simple. vided to the Middle; and Compound, when it is Compound. divided into several Parts, each resembling a fimple Leaf. Thus when a Leaf is divided into three Simple ones, it is call'd Trefoil; if into five, Cinquefoil, &c. or they are faid to be trifoliated, quinquefoliated, &c. Pennated Leaves are fuch as are Pennated. divided into feveral Parts, like Lobes, placed along the middle Rib, either alternately, or by Pairs; as in Goat's-Rue, Agrimony, &c. A Ramofe Leaf is that which is divided into feveral minute Branches; as in Ofmund Royal, Female Fern, &c. An Intire Leaf is that which has no Intire. Divifion on its Edges; as in the Apple-tree, &c. A Sinuated Leaf is that which is cut about the Sinuated. Edges into feveral large Segments; as in the common Mallow. A Serrated Leaf hath Edges Serrated. divided like the Teeth of a Saw; as in the Net

Ramofe.

tle, &c. A Crenated Leaf is that which is cut Crenated. about the Edges into feveral obtufe Segments; as

in Betony, &c. A Laciniated Leaf is that which Laciniated. is cut about the Edges into Jags, or deep Portions, in an irregular Manner; as in the Horned Poppy, &c.

THE Leaves are protruded from the Stalk or The Vegetation Stem by the great Quantities of vernal Sap, in of Leaves. the Form of a Gem or Bud, wherein they lie curiously folded in Plaits, and feparated from each other by a fine Pellicle or Membrane. The

Sap

Of the Flower of Plants.

Parts of a perfect one. Empalement.

Petala.

Stamina.

Apices.

Stylus.

Ovarium.

Sap arifing now in great Abundance, enters andi fills the Veffels of the tender Leaf; this caufes it to expand and extend itself quickly to its juft or defigned Limits of Growth. The Afflux and Reflux of the nutritious Juices by the Foot-Stalk of the Leaf continuing a while, at length abates and declines, the Juices then in the Leaf begin to stagnate and grow putrid, whence a Confumption enfues, and the Leaf dies; which is the Caufe of the Falling of the Leaves in Autumn.

THE FLOWER is that Part of a Plant whofe curious Form, charming Fragrance, and beauteous Colours fo delight our Senfes. This is certainly the most choice and delicate Part of Vegetables. A perfect Flower is faid to have the following Parts; (1.) The Empalement, Calix, or Flower-Cup; this is that exterior Part which enclofeth the Lower-part of the Flower, and is therefore alfo call'd the Perianthum; its Ufe is to strengthen and preferve the Flower. (2.) The Petala or tender fine-colour'd Leaves, which are generally the moft confpicuous Part of the Flower; this is alfo call'd the Foliature. (3.) The Stamina or Chives, which are those fine upright Stems which stand immediately within the Feliature, and in many Plants they arife from the Petala or Flower-Leaves. (4.) The Apices or Summits, which grow on the Top of the Chives in the Form of Seeds, and contain a fine Powder or Duft call'd the Farina or Meal of the Flower. (5.) The Stylus or Pistil, which ftands in the Middle, within the Chives, whofe Top is fometimes above, but generally below the Apices, and grows on (6.) The Matrix or Ovary, or Seed-Cafe, in which the Seed (in moft Plants) is contain❜d and nourish'd in its Embryo-State; and this Part is generally the Rudiment of the Fruit.

The

The Flowers which want any of these Parts are reckoned imperfect ones.

Parts of

THERE is, as I have before obferved, in Plants as well as Animals, a Difference of Sex, Of the Sex and the Flowers are the Pudenda or Organs of and Genital Generation in each Plant. The Male Parts of Plants. the Flower are the Stamina, which bear the Apices; and thefe, as Tefticles, contain the prolific Powder or Sperm of the Plant. The Female Parts are the Style, which ferves as a Vagina to receive and convey the spermatic Farina of the Apices to the Seed-Cafe, which is the Matrix or Womb; by which means the Embryo-Seeds are impregnated with the prolific Power of producing a future Plant.

Flowers.

FLOWERS are therefore fome Male, fome Of Male, Female, and others Hermaphrodite. The Male Female, and Flowers have the Stamina and Apices, but bear Hermaphrodite no Fruit, and are therefore call'd Stamineous Flowers. The Female Flower bears the Style or Piftil, which is fucceeded by the Fruit. These Male and Female Flowers grow at fome Distance from each other on many Plants, as Cucumber, Melon, Gourd, Turky Wheat, Turnfol, Wallnut, Oak, Beech, &c. Hermaphrodite Flowers contain both Male and Female Parts, and are by far the greatest Tribe, as Tulips, Lilies, Daffodil, Althea, Rofemary, Sage, Thyme, &c.

THERE is a large Diftribution of Flowers into Monopetalous, Dipetalous, Tripetalous, Tetrapetalous, &c. according as they confift of one, two, three, four, &c. Petala or Leaves; but this is not worth any further Regard here.

THE FRUIT is that Part of a Plant which of the Fruit fucceeds the Flower, and is defigned to contain, of Plants. preferve, nourish, and defend the Seed. Hence, in the Texture of this Part, the more coarfe and lefs concocted Parts of the nutritious Juices are filtred,

Gg