branch bears an anther of the usual structure, which, together with the central one, augments the number to 10. In the female flower, the styles are 3, united at the base, and the stig mas are divided into two lobes. The fruit is 3-sided and 3-celled, each cell containing two seeds placed parallel, and opening at the angle by a longitudinal suture; these sutures are immediately perpendicular to the styles, and placed opposite the exterior segments of the calyx. I ought to have before remarked, that the form and structure of the anthers of Euphorbia and Empetrec are exactly similar. The monophyllous calyx; the non-separation of the sexes; the presence of a perigynous disk; and the flat, somewhat foliaceous cotyledons,-appear to separate sufficiently the Celastrina from the Empetrea. The distinctions between them and the Rhamnee are still more apparent, however; for in them, the stamens are placed opposite the petals, and the æstivation of the calyx is valvular,—characters of primary importance in a natural classification. The embryo in Rhamneæ and Celastrinæ agrees exactly in form and structure. Mr Brown has very properly placed Phylica among the Rhamneæ, although I have known some who, merely from the fruit being inferior, were disposed to remove it from that family. It is evidently intimately allied to Pomaderris, both in habit and characters, and it is equally evident, that the fruit being inferior, is a distinction more apparent than real; for in Pomaderris, and even in some species of Rhamnus, the tube of the calyx coheres with the ovarium; and could we, for example, suppose an equal elongation of the tube of the calyx in these, as in Phylica, we should then have the situation of the fruit precisely the same. The apparently simple stigma in Phylica is not very different from the triple one of Pomaderris; for there is evidently an indication of three distinct lobes.

MASC.-Calyx 3- (rarò 2-) phyllus, æstivatione imbricatâ, basi nudus v. squamis (4-6) duplici ordine imbricatis munitus. Petala 3 (rarò 2) hypogyna, foliolis calycinis alterna, ungui brevi,

limbo obovato concavo erosè crenulato, marcescentia. Stamina totidem, iisdemque alterna, hypogyna, exserta, paululum interiùs seposita, pariter marcescentia: filamenta longiuscula, angustissima, compressa, glabra: antheræ subrotunda, biloculares, subdidymæ, ad medium peltæ modo filamentis imposita: loculis ventricosis, ferè omnino solutis, rimâ longitudinali exteriùs dehiscentes. Ovarii rudimentum. FEM.-Calyx maris. Petala totidem, sed breviora et vix unguiculata. Staminum rudimentis rarò ullis. Pistillum: ovarium globosum, sessile, disco carnoso impositum, 3, 6, v. 9-loculare, ovulis solitariis: styli 3, brevissimi, in unum corpus triangulare coaliti: stigmata radiato-multifida: lobis 6 v. 9, patulis, basi dilatatis, subtùs percurrenti-carinatis, suprà sulco perangusto exaratis, pruinosis, apice truncatis, emarginatis v. bicorniculatis. Bacca sphærica, nunc depressa, apice leviter umbilicata, basi calyce persistente cincta, 2, 3, 6 v. 9-pyrena: caro parca: pyrenæ testâ osseâ monospermæ, erectæ, collaterales, elliptico-trigonæ, compressiusculæ, columellæ demum evanescentis angulis numero æqualibus per totam longitudinem adnatæ, dorso convexo sulcato, ad apicem puncto exiguo ferè perviæ. Semen ovoideum, cavitati pyrenæ conformis, basi chalazâ tuberculiformi atro-fuscâ instructum: testa simplici, membranaceâ, spadiceâ, reticulato-vasculari, apice puncto notatâ: albumen copiosissimum, densum, carnosum, aqueo-pallidum, hinc facie planiusculâ, inde convexum. Embryo teres, erectus, axilis, lacteus, albuminis ferè longitudine: cotyledones semicylindricæ, obtusæ, arctè applicatæ radicula infera, recta, cylindracea, obtusa, cotyledonibus ferè triplo longior.

Frutices (utriusque orbis zonis temperatis proprii) humillimi, sempervirentes, facie ericoidea. Folia alterna, petiolo exigui complanato suffulta, margine revoluta, integerrima, exstipulata. Flores parvi, axillares solitarii, v. terminales glomerati.

EMPETRUM.

EMPETRI sp. Linn. Juss.

Calyx 3-phyllus, coriaceus, basi squamis 6 imbricatis munitus. Petala 3. Stamina 3. Stigma 6-9-fidum. Bacca depressa, 6-9-pyrena.

Fruticuli (Europ. bor. et Magellan.) ramosissimi, procumbentes. Folia alterna, lineari-lingulata, obtusa, suprà plana, subtùs convexa et linea membranaceâ exarata, atro-viridia, nitida. Flores axillares, solitarii, sessiles, atro-sanguinei. Baccæ nigræ v. rubræ. Hùc E. nigrum, L. et E. rubrum, Vahl.

1

COREMA.

EMPETRI Sp. Linn. Juss.

Calyx 3-phyllus, membranaceus, basi nudus. Petala 3. Stamina 3. Stigma 6-fidum. Bacca globosa, 3-pyrena

Suffrutex (Europ. austr.) erectus, ramosissimus, rigidus, punctis resinosis adspersus. Folia undique sparsa, linearia, obtusa, patula, suprà planiuscula, margine revoluta. Flores terminales, glomerati, sessiles, disco piloso impositi, albi, majores. Capitula squamis villosis bracteolata. Baccæ alba.

Hùc E. album, L,

CERATIOLA, Rich. in Mich. Fl. Amer. bor.

Calyx 2-phyllus, membranaceus, basi squamis 4 munitus. Petala 2, in tubum conniventia. Stamina 2. Stigma 6-fidum. Bacca globosa, 2-pyrena. Suffrutex (Amer. bor.) adscendens, ramosissimus, rigidus. Rami stricti, simplices. Folia alterna, patentia, acerosa, obtusa, glabra, nitida, viridia, subtùs sulco angustissimo exarata, suprà leviter canaliculata, semipollicem longa; nunc plurima approximata, quasi verticillata. Flores axillares, sessiles, plures (2-4), rarò solitarii; nunc (ad folia approximata scilicet) verticilli modo dispositi. Baccæ rubræ ?

Hùc Ceratiola ericoides, Rich. in l. c. 2. p. 221.

In order to render this treatise as complete as possible, besides giving a description of the group itself, I thought it important to add the characters of the genera. It is immaterial whether the Empetrece are to be regarded as a section of the Euphorbiacea, or as constituting a separate family. Their intimate affinity has, I trust, been satisfactorily shewn; and it also appears clearly evident, that the Euphorbiaceae, Stackhouseæ, Celastrinæ, and Rhamneæ, must follow each other in a natural arrangement, as Mr Brown seems disposed to think *.

* General Remarks on the Botany of Terra Australis.

Establishment of Vegetation at the Surface of the Globe *. WE have seen vegetation covering, with verdure and flowers, all parts of our globe; we have seen it extending itself from the bottom of the valleys to the most elevated places, resisting, in the plains, the burning rays of the sun, struggling upon the mountains with the frosts, bursting forth every summer from beneath the snows, and only stopping short at the zone of perpetual ice. But how does this vegetation come to cover the nakedness of rocks, to fix the mobility of sands, to implant itself in the strong gravel, to convert immense lakes into marshes, and these again into forests and fields? for such was, and such still is, the surface of the globe, in all places destitute of vegetation, whether in islands which have newly sprung from the bosom of the waters, or in tracts where the soil has been overturned by particular accidents, or deprived, by other circumstances, of their ancient verdure; such, also, do we find it, if we remove the layer, more or less thick, of earth which clothes it. This earth is, therefore, of new formation, as well as the vegetation which it supports; it has not been formed simultaneously with the rock on which it rests, or with the bed of sand which it covers.

This important observation is commonly overlooked. Accustomed to see the same flowers re-appear at each return of spring, the same meadows clothed again in fresh verdure, we scarcely

* Of all the branches of Natural History, undoubtedly Botany is that which has hitherto (mineralogy and geology now dividing with it the public attention), in Britain, been the most generally cultivated: hence every where we find splendid gardens and conservatories; and numerous works on botany are daily issuing from the press. Distinguished botanists have not been wanting in England: and Scotland, although behind in this science, has given to England several young, intelligent, and active botanists,-to Europe its greatest botanist, our illustrious countryman Brown: but, strange to say, the only naturalists who have actively embarked in the botany of Scotland, have been principally Englishmen or foreigners. Scotland offers still a fine and unexplored field to the philosophic botanist,—in the investigation of the physical and geographical distribution of its land and aquatic plants. He who shall undertake this highly interesting investigation, must be intimately acquainted with the facts and reasonings of meteorology and hydrography,— with the details and views of geology; and the ardent inquirer into the geography of plants cannot expect to illustrate it, without also knowing the natural history of animals; and, finally, he must be familiar with the use of the barometer, and other instruments.-EDIT.

reflect upon the origin of this beautiful and abundant vegetation, or rather referring it to the period of the general creation of beings, it seems to us to lose itself in the mysterious obscurity of the formation of the universe; and we thus find ourselves discharged, as it were, from the task of inquiring, by what means nature has everywhere diffused this precious mould, the source of riches and of life, and which yet is but the residue of generations heaped upon generations. Here an objection presents itself, which appears, in part, to destroy what I have advanced. If vegetable earth, it may be said, is necessary to the existence of plants, it must have been created previously to their existence, and can only receive what it had itself furnished them.

Such has been the error, which, during a long series of ages, has prevented our understanding one of the greatest operations of nature, and which, although continually before our eyes, has only escaped our observation from the little attention which we have bestowed upon an order of plants considered as little worthy of regard from their homeliness of aspect, their diminutive size, and the simplicity of their composition; but when the piercing eye of genius determined their relations in the natural order of things, when it recognised the functions which they had to fulfil, and the rank which they occupy in the general system of vegetation, they assumed a character of grandeur, which directed the attention toward their existence. It has been discovered, that, so far from requiring vegetable earth for their subsistence, they have furnished it by their decomposition, in small quantity it is true, but yet sufficient for the reception of plants of an order somewhat higher, and to which, in proportion as the vegetable earth increases, succeed vegetables much more vigorous.

To explain what we have to say upon this subject, we must fix our notice, for a moment, upon those plants which I have said to be the basis of vegetation. Although very common throughout nature, they have scarcely been remarked. They everywhere invest walls, rocks, humid places, and the trunks of trees; they attach themselves to all substances, however little they may be favoured by circumstances. The rays of the sun, and dry and cold winds, are as much inimical to them, as shade and humidity are favourable. These plants bear the names of conferva, byssi, and lichens. To them succeed mosses, hepatica, lycopo OCTOBER-DECEMBER 1826.

E