[Illustration] USEFUL KNOWLEDGE. ---- VEGETABLE PRODUCTIONS. ---- _INTRODUCTION._ 1. VEGETABLES or PLANTS are natural bodies endowed with organization and life, but destitute of voluntary motion and sense; and BOTANY is that branch of natural science which treats of their structure and functions, the systematical arrangement and denomination of their several kinds, and their peculiar properties and uses. 2. The principal parts of plants are the _root_; the _herb_ or plant itself; and the _fructification_, or flower and fruit. 3. As it is the sole object of this introduction to describe, in a concise manner, the Linnæan arrangement of plants, for the purpose of explaining the classification adopted in the present volume, the parts of _fructification_ only will be mentioned. These are the calyx, corolla, stamens, pistil, seed-vessel, seeds, and receptacle. 4. The CALYX, or flower cup, is the green part which is situated immediately beneath the blossom. In some plants this consists of one, in others of several leaves; and it is frequently tubular, as in the polyanthus, and cowslip. 5. The COROLLA, or blossom, is that coloured part of every flower on which its beauty principally depends. The leaves that compose it are denominated _petals_. Some flowers, as the convolvolus and campanula, have only a single petal; and others, as the rose and peony, have several petals. 6. In the centre of the flower there are two kinds of organs on which the fructification and re-production of the species more particularly depend. These are the stamens, and the pistil. The STAMENS are slender, thread-like, substances, which surround the pistil. They each consist of a _filament_ or thread, and an _anther_ or summit: the latter contains, when ripe, a fine dust or powder called _pollen_. This, though, to the naked eye, it appears a fine powder, is so curiously formed, and is so various in different plants, as to be an interesting object for the microscope. Each grain of it is, commonly, a membranous bag, round or angular, rough or smooth, which remains entire till it meets with any moisture; it then bursts and discharges a most subtile vapour. 7. The PISTIL is a prominent part, immediately in the centre of each flower, which adheres to the fruit, and is destined for the reception of the pollen. Some flowers have only one pistil; others have two, three, four, &c. and others more than can be easily counted. 8. At the foot of the pistil is situated the _germen_. This, when grown to maturity, has the name of pericarp or SEED-VESSEL, and is that part of the fructification which contains the seeds: whether it be a _capsule_ as in the poppy, a _nut_ as the filbert, a _drupe_ as the plum, a _berry_ as the gooseberry, a _pome_ as the apple, a _pod_ as in the pea, or a _cone_ as of the fir-tree. 9. That part of every vegetable, which, at a certain state of maturity, is separated from it, and contains the rudiments of a new plant, is called the SEED.