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What Worms Do.—The main purpose of Mr. Darwin's new book is to show that what is generally called "vegetable" mould is almost solely the work of worms, and is, therefore, more animal than vegetable. The Times, in an appreciatory review of the work, says,—They are constantly swallowing earth and tiny stones, and passing them through their bodies to the surface in a finely triturated and fertilised condition; in fact, they may be said to manure the earth inside their own bodies. By means of this process the entire earthy surface of a country is constantly in a state of change. The whole earth underneath our feet all over the world is swarming with worms; probably all over there are in every acre of land from 35,000 to 50,000 worms. Every one is familiar with the casts of worms, which themselves look like worms of earth. With so many worms at work, then, it is not difficult to imagine what will be the effect of a constant accumulation of such casts. In some cases, if spread over the ground, they would measure 1/5 in. in depth per year equal to 1 in. of earth brought up from below, passed through the bodies of worms, and deposited on the surface in five years. In one instance given by Mr. Darwin, 12 oz. of castings were thrown up in a year on a square foot, or 6.75 lb. on the square yard, equal to 14 1/2 tons of so-called fertile "vegetable" mould over an acre in one year. Leaves, and stones, and lime, and other substance spread over a field, and left untouched, have been found in a very few years several inches below the surface, in a uniform layer. This, there can be no doubt, from the multitude of data supplied by Mr. Darwin, is all the work of worms. The millions of leaves and other vegetable matter dragged by the persevering creatures underneath the soil, whether passed through their bodies or not, form a splendid natural manure.