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FLORA ANTARCTICA.
[Fuegia, the

with the Juan Fernandez plant. St. Hilaire and Cambessèdes describe four and give figures of three varieties; herein they differ from Martius, who considers it the same as D. Winteri, but these authors do not state their reasons ('Plantes Usuelles de Brésil,' Tab. 26-28), and neither in the plates or descriptions do any characters appear which are not common to some of the Chilian and Fuegian specimens: their var. sylvatica coincides with Juan Fernandez specimens; the var. montana has smaller leaves than any found on the west coast of the continent. Chamisso and Schlechtendahl, in their notes upon the Mexican plant collected by Schiede and Deppe, refer it to D. Granatensis (Linnæa, vol. v. p. 210; vol. vi. p. 417; and vol. x. p. 214.); it is identical with D. Mexicana, Mor. and Sesse, (Pl. Mex. in DC. Prodr.), and some of the Chilian examples agree with Mexican ones. The effuse panicle and larger flowers are more characteristic of the northern states of the tree, but these peculiarities afford no specific distinction. A singular state, with small narrow leaves, remarkably revolute at the margins, has been gathered in Brazil by Claussen. The variations in the foliage are too gradual to admit even of the forms being grouped into varieties indicative of countries or of other peculiarities, and the glaucous hue of the under surface of the leaves is equally apt to mislead.

I feel little doubt that this plant extends over no less than 86° of latitude, forming at the southern limit of its growth one of the three trees that advance the nearest to the Antarctic circle, and reaching as high a latitude as any flowering plant, save the solitary grass of the South Shetland Islands. No vegetable production of its size affords a parallel case to this, either in America or any other country. Such an extraordinarily extended range is in part obviously due to some peculiarities in the form and surface of South America, where under every degree of latitude there are large areas either at the level of the ocean or at an elevation where such a tree can enjoy a climate that is equable. To the influence of the like causes I should attribute the specific identity between some high northern and southern species, which like the Gentiana prostrata, Trisetum subspicatum, and other plants mentioned in the former part of this work (Part i. p. 117), pass along the Andes from the northern temperate or frigid point to the southern extreme of America.

The Drimys Winteri is one of those plants which is represented by two closely allied species in other quarters of the globe, one in Tasmania, the Tasmania aromatica, and the Drinys axillaris in New Zealand. There are many instances of genera having representatives in those three botanical regions, the species being in general mutually more related than to any others, such are afforded by the genera Fagus, Astelia, Abrotanella, by shrubby Veronicas and many others. This similarity in some of the botanical productions of countries, otherwise unlike in vegetation, is far more remarkable than a total dissimilarity between lands so far separated, or even than a positive specific identity woidd be at first sight; because it argues the operation of some agent far above our powers of comprehension, and far other from what we commonly observe to affect geographical distribution.

III. BERBERIDEÆ. Vent.

1. BERBERIS, Linn.

1. Berberis ilicifolia, Forst.; erecta, spinis tripartitis, foliis obovatis grosse spinoso-dentatis, pedunculis folio brevioribus 4-6-floris, pedicellis elongatis subcorymbosis, floribus majusculis, baccis late ovatis lagenæformibus. B. ilicifolia, Forst. Comm. vol. ix. p. 28. Linn. Fil. Suppl. p. 210. DC. Syst. vol. li. p. 12. Prodr. vol. i. p. 107. B. lagenaria, Poir. Dict. vol. viii. p. 619. (Tab. LXXXVI.)

Hab. Strait of Magalhaens on both sides and throughout Fuegia; Commerson, Forster, and all future collectors.

This is certainly the handsomest species of the genus, forming a straggling bush, eight feet high, with deep