The summits of the Torres and Torrinhas are nothing but barren naked rocks,--not a blade of grass, not a shrub, not a trace of vegetation is to be seen. At the highest points, strata nearly horizontal extend in remarkably regular layers, chiefly distinguished by the most manifold variety of colours and tints.[33] A dark grey schistus of volcanic ashes alternates with strongly-marked red, yellow, and violet layers of tufa, dross, and scoriæ, together with brown and grey conglomerates. Just as red predominates on the upper part of these _Torres_, green prevails on the lower. From the spot where the springs first issue out of the crevices of the basalt, everything seems covered with a dense green carpet. These are the celebrated "clefts" of Madeira, in which, even on rocks of 1000 feet high, not an inch is to be discovered bare; they afford a rich harvest to the botanist, whilst they fill the spectator with delight and admiration. [Footnote 33: The celebrated American geologist, Mr. Dana, mentions that these wild contorted masses of mountain reminded him of the crater-walls of the Kilauea at the Sandwich Islands.] [Illustration: ERICA TREES.] Generally speaking, the scenery of Madeira does not owe its character to the grandeur or magnitude of its trees; the peculiar charm of the landscape arises more from grasses, ferns, shrubs, and different kinds of moss, all of which grow so rank and luxuriant, that the rocks, chasms, and abysses overgrown with them, appear like so many swelling cushions, or as if laid with soft velvet carpets in all directions. The different shades of green indicate the characteristics of successive zones of vegetation. Through the lower parts of the valleys run the beds of those mountain waters which, though nearly dried up in the summer, swell in the winter into torrents. Along these are scattered the straw-thatched huts of the natives, surrounded by vineyards and fields planted with rye, barley, potatoes, yams, and in the lower parts with single bananas. These cultivated lands rise to a height of 2000 feet, and in many places even to 3000. Wherever on the steep declivities there is the smallest shelf to be found, even if only a square yard in size, it is turned to account. Next to this region, in ascending, is that of the brush and laurel woods. _Vaccinias_ (blackberries), and different kinds of heath, often attaining a growth of five or six feet, occupy the whole of the ground, and in the month of June, when the broom is in full flower, a bright golden-coloured belt girts Madeira, at a height of from 3000 to 4000 feet. We beheld this golden girdle in its richest splendour, set off by the dark masses of evergreens in the clefts. Higher up is the true region of the _Erica arborea_, which, with its light-green and _paille_ tint, contrasted with the deeper colour of the laurel, represents the underwood of our secondary mountain ranges. The _Erica arborea_ attains here the height of a large