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Vegetable Mould and Earth-worm is the subject of Mr. Darwin's latest publication. Its object is to show the influence of these animals upon the formation of humus from the original rocks of the earth, and from the vegetable growths of the present and to show how, especially in cultivated land, their presence tends to benefit the soil by enriching it and rendering it more readily permeable by water. Although Mr. Darwin's enthusiasm has perhaps carried him too far in some of his conclusions, his work will, nevertheless, prove valuable to the scientist, affording, as it does, the results of nearly half a century's patient investigation upon the habits of this species of the annelids, of which so little was formerly known. The amateur in science will find in it a source of profitable recreation, as the author has made use of quite familiar and untechnical terms. The results of Mr. Darwin's calculations are in some cases quite astonishing. Such, for, instance, is the statement of the existence of nearly thirty thousand (30,000) earth-worms in every acre of cultivated land. The work that so great a number of animals can perform is enormous, and is the more evident when we consider the comparatively great muscular strength of the earth-worm. We are informed that the food of the earth- worm consists chiefly of the partially decayed organic matter of the soil; and to obtain the nutritive portion.

The worm swallows the earth as he finds it at the bottom of his burrow. The indigestible portion is deposited at the mouth of the burrow. It is thus that the principal work of the earth-worm is accomplished, the mould being turned over, as if by a plow, every few years. Nor does the antiquarian owe less to the earth-worm than does the agriculturalist. For many ruins of old walls, pavements and buildings have been covered up, and thus preserved for ages, by these indefatigable little servants of Nature. Mr. Darwin mentions the remains of several abbeys, and even Roman villas, towns and cities which have been hurled and concealed by the action of worms, aided, no doubt, considerably by the washing down of soil from the neighbouring higher lands, and by the deposition of dust. Ancient embankments and tumuli have also been somewhat lowered in the course of centuries, although their inclination may not have been greatly changed. In this way these lowly organized creatures have played an important part in the history of the world, and are, perhaps, rivalled by the corals alone, whose works, though more conspicuous, are far less useful. One can scarcely fall to be benefited by a perusal of this charming book, if only to be convinced that no creature is too unimportant to be of service in the world. Published by D. Appleton & Co. For sale by John Moore.