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ARBORETUM AND FRUTICETUM.

PART III.

has been, first, to study the subject historically, that is, to ascertain what hasbeen said of it in books; and, next, to study it practically, that is to comparethe information and the plates given in books, with living plants. Afterperusing all the works we could procure on the subject, including Lambert’sGenus Pinus, 2d edit., 2 vols, 8vo, and the third volume of that work (which,though only three or four copies have yet, August, 1837, been published,we have been very kindly favoured with the loan of by His Grace the Dukeof Bedford), we took the first two volumes of Lambert’s work, and thatvolume of Michaux’s North American Sylva which contains the dbietinae ofNorth America, in our hands, and visited Loddiges’s arboretum, the Horti-cultural Society’s Garden, Kew, Syon House, Dropmore, Whitton, PainsHill, Mill Hill, White Knights, and the principal nurseries; and, from the studyof the plants in these places, in connexion with the descriptions and platesin the books we have mentioned, we have arrived at the general conclusionswhich we shall now shortly lay before the reader, as preliminary to giving eachgenus, and its species and varieties, in detail.

In every arrangement of species and varieties, it appears to us that thereought to be two objects in view. First, to throw all the kinds into groupscapable of being more or less distinctly defined; or, at all events, of being repre-sented by one species as a type; such, for example, as the group Sylvestres,of the section Binae, which consists of species all more or less resembling theScotch pine in foliage and in cones. The use of these groups is, to renderthe whole mass easily comprehended by any person who knows only a few of thespecies ; and, secondly, when separating these groups into species and varieties,to give as prominent a place to all varieties and subvarieties that are truly dis-tinct, as if they were species. Besides the argument which we have advanced infavour of throwing the kinds into groups, there are the important ones men-tioned in Part II. of this work (p. 216.) ; viz. those of assisting a collector oftrees to make a judicious selection, and of preventing a beginner in botanicalstudies from puzzling himself in finding out specific distinctions where nonereally exist. The reason why we wish to keep every variety and subvarietyas distinct as possible is, that, in the practice of arboriculture, whether foruseful or ornamental purposes, a variety is often of as much importance as aspecies, and sometimes, indeed, more so : for example, in P. sylvestris, theHighland variety is known and acknowledged to produce timber of a superiorquality to the common kind; and, in point of ornament, for situations wherethe common kind of Scotch pine is too large, the species may be repre-sented by P. (s.) p. Mughus nana, which forms a beautiful little bush.

In studying the /fbietinas from living trees, the terminal buds, the numberof leaves in a bundle or sheath, and their position on the branch, the sheathsbeing persistent or deciduous, and the form of the cones, and the characterof their scales, are the principal points by which, we think, one species or groupof kinds can be distinguished from another. Thus, in Pinus, all the varieties ofP. sylvestris have short-pointed resinous buds, differing less in this respectthan they do in their cones, or in the length of their foliage. P. Larido(which we consider as including a number of European and some Asiatickinds, generally ranked as species, such as P. taurica, P. romana, P. cala-brica, P. caramanica, &c.) is distinguished by its long, sharply pointed, con-cave-sided, resinous buds; and P. Pinaster and P. Pfnea, by their short,blunt, imbricated buds, which are never covered with resin. The buds ofP. Pfe'da (which we consider to be the centre of a group of varieties generallytreated as species, under the names of P. rigida, P. variabilis, P. serotina, &c.)are very small and resinous, and they are more numerous on the shoots than inany other species, either European or American. All the kinds belonging toP. Pae'da have also the peculiar property of sending out numerous small abor-tive shoots from the dormant or adventitious buds in their trunks and largerbranches, by which the trees may be known at a glance, even at a distance.All the tender kinds (such as P. longifolia, and its allied sorts, P. leiophylla,P. canariensis, &c.) have small obscure buds; and so on. The scales of