Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 3, 1802).djvu/413

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which, on adding different ingredients, either assumed various shades, or remained unaltered; so that they may with advantage be employed in dyeing.

PLANT, an organic fibrous body, consisting of roots and other parts: though capable neither of sensation, nor spontaneous motion, it attaches itself to other bodies, in such manner as to derive nourishment from them, and to propagate itself by seeds.

The constituent parts of plants are the roots, stems, branches, rind or bark, leaves, flowers, and seeds; which greatly vary, both in figure and size, according to the nature of particular trees, shrubs, &c.: as, however, the principle of vegetation is throughout analogous, we forbear to enter into a minute description of the various appearances, that have induced botanists to divide the vegetable kingdom into orders, classes, genera, species, and varieties.

All plants, however minute, are propagated by seed: and so easy is their cultivation, that in many instances they may be reared by parting their roots, or depositing layers, cuttings, &c. of the parent-stock, in such soils as are most congenial to their nature. Hence botanists consider them as an inferior class of animals; a conjecture, that is strongly corroborated by the regular circulation of the sap throughout all their parts; and by the sleep of plants, or the faculty which they possess of assuming, at night, a position different from that in which they appeared during the day.—This opinion, respecting the animal life of plants, has been carried to a still greater extent, by an eminent philosopher, whose name we have frequently cited, and who has minutely described the absorbent and umbilical vessels; the pulmonary and aortal arteries; as well as the veins, muscles, nerves, brain, and other parts relative to the physiology of vegetation.

Consistently with, and prior to the Linnæan classification, plants have been divided into male, that is, such as produce no fruit, possessing only the farina; and into female, or those which bear fruit, and also have the pistil, while they are destitute of the farina. And, as the fecundating dust is specifically heavier than the air, provident Nature has so arranged their organization, that in those plants, the pistils of which are larger than the stamina, the flowers are spontaneously nodding, in order that the farina may be more easily received. For a similar purpose, in aquatic plants, or such as naturally vegetate under water, the flowers emerge above the surface a short time before they blow. There are, however, many vegetables, in which the anthers or males bend into contact with the stigmas or females; and, as the former recede, others approach.—We could pursue this account of the amatorial attachment of plants to a greater extent, if it were compatibie with the design of this work.—See also Botany; Bulb; Leaves; Planting; and Tree.

PLANT-LOUSE, Puceron, or Vine-fretter, Aphis, L. a genus of insects, comprising many species and varieties, and of which are denominated from the plants they infest. Their rostra or beaks are inflected; they are provided with four erect wings; and the abdomen terminates in two horns,

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