The form of Ferns,[28] as well as that of Grasses, becomes ennobled in the hotter parts of the globe. Arborescent ferns, when they reach a height of above 40 feet, have something of a palm-like appearance; but their stems are less slender, shorter, and more rough and scaly than those of palms. Their foliage is more delicate, of a thinner and more translucent texture, and the minutely indented margins of the fronds are finely and sharply cut. Tree ferns belong almost entirely to the tropical zone, but in that zone they seek by preference the more tempered heat of a moderate elevation above the level of the sea, and mountains two or three thousand feet high may be regarded as their principal seat. In South America the arborescent ferns are usually found associated will the tree which has conferred such benefits on mankind by its fever-healing bark. Both indicate by their presence the happy region where reigns a soft perpetual spring. I will next name the form of Liliaceeous plants,[29] (Amaryllis, Ixia, Gladiolus, Pancratium) with their flag-like leaves and superb blossoms, of which Southern Africa is the principal country; also the Willow form[30], which is indigenous in all parts of the globe, and is represented in the elevated plains of Quito, (not in the shape of the leaves but in that of the ramification), by Schinus Molle; Myrtaceæ[31], (Metrosideros, Eucalyptus, Escallonia myrtilloides); Melastomaceæ[32], and the Laurel form[33]. It would be an enterprise worthy of a great artist to study the aspect and character of all these vegetable groups, not merely in hot-houses or in the descriptions of botanists, but in their native grandeur in the tropical zone. How interesting and instructive to the landscape painter[34] would be a work which should present to the eye, first separately and then in combination and contrast, the leading forms which have been here enumerated! How picturesque is the aspect of tree-ferns spreading their delicate fronds above the laurel-oaks of Mexico; or groups of plantains over-shadowed by arborescent grasses (Guaduas and Bamboos)! It is the artist’s privilege, having studied these groups, to analyse them: and thus in his hands the grand and beautiful form of nature which he would pourtray resolves itself, (if I may venture on the expression) like the written works of men, into a few simple elements.