Page:Aspects of nature in different lands and different climates; with scientific elucidations (IA b29329668 0002).pdf/206

 *[Footnote: The Escallonia floribunda offers in its geographical distribution one of the most striking examples, in the habitat of the plant, of proportion between distance from the equator and vertical elevation above the level of the sea. In making this statement I again support myself on the authority of my acute and judicious friend Auguste de St.-Hilaire (Morphologie végétale, 1840, p. 52):—"Messieurs de Humboldt et Bonpland ont découvert dans leur expédition l'Escallonia floribunda à 1400 toises par les 4° de latitude australe. Je l'ai retrouvé par les 21° au Brésil dans un pays élevé, mais pourtant infiniment plus bas que les Andes du Pérou: il est commun entre les 24°.50´ et les 25°.55´ dans les Campos Geræs, enfin je le revois au Rio de la Plata vers les 35°, au niveau même l'ocean."

Trees belonging the group of Myrtaceæ,—to which Melaleuca, Metrosideros, and Eucalyptus belong in the sub-division of Leptospermeæ,—produce partially, either where the leaves are replaced by phyllodias (leaf-stalk leaves), or by the peculiar disposition or direction of the leaves relatively to the unswollen leaf-stalk, a distribution of stripes of light and shade unknown in our forests of round-leaved trees. The first botanical travellers who visited New Holland were struck with the singularity of the effect thus produced. Robert Brown was the first to show that this strange appearance arose from the leaf-stalks (the phyllodias of the Acacia longifolia and A. suaveolens) being expanded in a vertical direction, and from the circumstance that the light instead of falling on horizontal surfaces, falls on and passes between vertical ones. (Adrien de Jussieu, Cours de]*