LITERARY NOTICES.
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The investigations of De Candolle assume a new and enlarged interest from the results of modern biological progress in regard to the transformations of species, and the vast periods of time during which organic development and mutations have been going forward. The great problem was fundamentally changed with the abandonment of the old view regarding the immutability of species. It was under the careful study of plants that that view first broke down, and from that time a radically new method has prevailed in the study of the vegetable kingdom. From this point of view the historical question of the origin of cultivated plants not only became a modern question, belonging, indeed, to the present age, and incapable of earlier solution, but it connects itself with vast periods of change, and is linked on to the largest considerations of the economy of life upon the earth. We quote some further instructive observations of our author in regard to important particulars of his research:
From these considerations it will be seen that the present volume is of capital interest to all concerned with botanical science. It is an authoritative digest of facts to be nowhere else found, and has been executed with the strictest fidelity to the original sources of information. The fullness and minuteness of the references to works consulted greatly enhance the scientific value of the volume, and will undoubtedly be much appreciated by botanical students.
But, as we remarked at the outset, the book is entirely popular, and thoroughly intelligible to common readers. Its plan is simple. Part I consists of two chapters of general preliminary remarks as to I, "In what Manner and at what Epochs Cultivation began in Different Countries"; and II, "Methods for discovering or proving the Origin of Species." In Part II, the main portion of the work, the divisions are simple and practicable, as follows: I, "Plants cultivated for their Subterranean Parts, such as Roots, Tubercles, or Bulbs"; II, "Plants cultivated for their Stems or Leaves"; III, "Plants cultivated for their Flowers, or the Organs which envelop them"; IV, "Plants cultivated for their Fruits"; V, "Plants cultivated for their Seeds." At the close there in a valuable table summing up the general results, which is followed by a careful index. All the