sizes, from 3 4 of an inch in diameter to minute grains and mere dust. Dr.
King 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
disintegrated 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 21 2 feet wide and 9 inches deep, had been made 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 11 2 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
embankments, formed by fragments of the castings that had been arrested
in their downward progress by irregularities of the surface, by stones,
twigs, &c. One little group of plants of _Anemone hortensis_ 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
bleached petioles, in comparison with those of other plants of the same
kind, where there had been no such accumulation. The earth thus
accumulated had no doubt been secured (as I have everywhere seen) by the
smaller roots of the plants. After describing this and other analogous
cases, Dr. King concludes: I can have no doubt that worms help greatly
in the process of denudation.
_Ledges of earth on steep hill-sides_. Little horizontal ledges, one
above another, have been observed on steep grassy slopes in many parts of
the world. The formation has been attributed to animals travelling
repeatedly along the slope in the same horizontal lines while grazing,
and that they do thus move and use the ledges is certain; but Professor
Henslow (a most careful observer) told Sir J. Hooker that he was
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