HORTUS BRITA'NNICUS. 



PART I. 



LINNEAN ARRANGEMENT. 



JL HE main object of the artificial system of botanical arrangement is to facilitate the discovery of the names 

 of plants. For this purpose some one organ, common to plants in general, is fixed on; and, according to 

 certain conditions in which this organ is found, individual species are referred to their places in the system, 

 as words, by their initial letters, are referred to their places in an alphabetical dictionary. 



In the progress of artificial systems different organs have been fixed on by different botanists; but those 

 which have been most extensively employed are the corollas by Tournefort, and the stamens and pistils by 

 Linnwus. The system of Tournefort has been a good deal employed in France, and may be considered as the 

 artificial system of that country ; that of Linnaeus has been employed in most other countries, and is justly 

 esteemed by far the most perfect artificial system which has hitherto been produced. It is, therefore, adopted 

 in this work. 



The application of the Linnean system in practice, Sir J. E. Smith observes, is, above all other systems, easy 

 and intelligible. Even in pursuing the study of the natural affinities of plants, this botanist affirms " that 

 .t would be as idle to lay aside the continual use of the Linnean system, as it would be for philologists and 

 ogicians to slight the convenience, and indeed necessity, of the alphabet, and to substitute the Chinese 

 character in its stead." (Introduct. to Sot.) " The student of the Linnean artificial system," he elsewhere 

 observes, " will soon perceive that it is to be understood merely as a dictionary, to make out any plant that 

 may fall in his way." (Gram, of Sot.) " If we examine," says Decandolle, "the artificial systems which have 

 been hitherto devised, we shall find the most celebrated of them, that which was proposed by Linnaeus, to 

 i>pssess a decided superiority over all others, not only because it is consistently derived from one simple prin. 

 ciple, but also because the author of it, by means of a new nomenclature, has given to his terms the greatest 

 distinctness of meaning." (Elements of the Philos. of Plants, by Decandolle and Sprengel.) Whether or 

 not subsequent advances in science may enable botanists to dispense with the Linnean system altogether, it 

 is not for us to affirm ; but in the mean time nothing can be more certain than that the Linnean system is the 

 jest leading arrangement for such a work as the present, in the existing state of botanical knowledge in 

 Britain. * 



According to the Linnean system all plants are furnished with flowers, either conspicuous or inconspicuous. 

 The plants with conspicuous flowers are arranged according to the number and position of their stamens and 

 pistils ; those with inconspicuous flowers are arranged according to the situation of the flowers on the plant, 

 or according to other circumstances in the plant itself. 



To discover the name of a plant by the Linnean system, therefore, all that is 

 necessary for a beginner is to possess a specimen of it in flower, and to be able 

 to know its different parts by the names given them by botanists. To discover the 

 class, order, and genus of a plant, it is only necessary to be able to distinguish and 

 name the different parts of the flower. These parts are : the calyx or cup (fig. 1. a), 

 which is that leaf, or those leaves, by which the flower is usually enclosed when in a 

 bud, and which, when the flower is expanded, appear under it. The corolla 

 (corona, a crown) is the colored leaf, or leaves, of a flower (fig. 1. b). The stamen 

 (or first principle of any thing) is the thread-like process, or processes, imme- 

 diately within the leaves of the corolla (fig. 2.) : it consists of two parts, the filament 

 or thread (a), and the anther (b) ; this anther contains what is called the pollen, or fructi- 

 fying meal (c). In the centre of the flower is the pistil (fig. 3.) : it consists of 

 three parts, the germen, or rudiments of the fruit or seed (a), the style (b), 

 and the stigma or summit (c), which crowns the style, and is destined to receive 

 I the fructifying pollen. 



The pistil and stamen are the essential parts of a flower. The corolla or the calyx may be 

 wanting, and yet the flower will be termed perfect, because the absence of those parts is no 

 obstacle to reproduction. Even the style and the filament may be absent without preventing the 

 formation or ripening of the fruit ; and there are many flowers which have the anther sitting close 

 to the corolla, &c., without a filament, and the stigma to the germen without a style ; but the 

 anther, the germen, and the stigma are essential. 



The seed is contained in the pericarp, or seed-vessel, which is the germen when grown to maturity. The 

 i name of the seed-vessel varies according to its form, substance, &c. ; but the word pericarp (pert, about, karpon, 

 | a fruit) is applicable to all its varieties. The receptacle is the base or medium which connects the other parts 

 I of the fructification. (Magazine of Natural History, vol. i. p. 233.) 



i The degree of knowledge conveyed by the following Table, and the preceding observations, will enable a 

 1 beginner to discover at least the class and order of any plant which he may find in flower. 



\ * The best work in the English language for acquiring a knowledge of the Linnean System of botany is 

 smith's Introduction to Botany, 1 vol. 8vo. The best work for acquiring a knowledge of the Natural System 

 is Lindley's Introduction to the Natural Orders, 1 vol. 8vo. Concise and familiar Introductions to both the 

 ' Linnean and Jussieuean Systems will be found in the Magazine of Natural History. 



