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Show 276 DENUDATION OF TilE LAND CHAP. VI. these castings are extremely liable to crumble during dry weather into small fragments, which are soon acted on by rain, and then sink down so as to be no longer distinguishable from the surrounding soil. He sent me a mass of such disintegrated castings, collected on the top of a bank, where none could have rolled down from above. They must have been ejected within the previous five or six months, but they now consisted of more or less rounded fragments of all sizes, from ! of an inch in diameter to minute grains and mere dust. Dr. l{ing witnessed the crumbling process whilst drying some perfect castings, which he afterwards sent me. Mr. Scott also remarks on the crumbling of the castings near Calcutta and on the mountains of Sikkim during the hot and dry season. When the castings near Nice had been ejected on an inclined surface, the di sintegrated fragments rolled downwards, without losing their distinctive shape; and in some places could " be collected in basketfuls." Dr. King observed a striking instance of this fact on the Corniche road, where a drain, about 2! feet wide and 9 inches deep, had been made CrrAP. VI. AIDED BY WOUMS. 277 to catch the surface drainage from the adjoining hill-side. The bottom of this drain was covered for a distance of several hundred. yards, to a depth of from 1! to 3 inches, by a layer of broken castings, still retaining their characteristic shape. Nearly all these innumerable fragments had rolled down from above, for extremely few castings had been ejected in the drain itself. The hill-side was steep, but varied much in inclination, which Dr. King estimated at from 30° to 60° with the horizon. He climbed up the slope, and "found every here and there little embank" ments, formed by fi·agments of the castings "that had Leen arrested in their downward "progress by irregularities of the surface, "by stones, twigs, &c. One little group of '' plants of Anemone lwrtensis had acted in this "manner, and quite a small bank of soil had "collected round it. Much of this soil had "crumbled down, but a great deal of it still " retained the form of castings." Dr. King dug up this plant, and was struck with the thickness of the soil which must have recently accumulated over the crown of the rhizoma, as shown by the length of the |