yet, satisfy all those requirements; but we do not hesitate to assert that it is as superior to any preceding or contemporary hypothesis, in the extent of observational and experimental basis on which it rests, in its rigorously scientific method, and in its power of explaining biological phaenomena, as was the hypothesis of Copernicus to the speculations of Ptolemy.  But the planetary orbits turned out to be not quite circular after all, and, grand as was the service Copernicus rendered to science, Kepler and Newton had to come after him.  What if the orbit of Darwinism should be a little too circular?  What if species should offer residual phaenomena, here and there, not explicable by natural selection?  Twenty years hence naturalists may be in a position to say whether this is, or is not, the case; but in either event they will owe the author of “The Origin of Species” an immense debt of gratitude.  We should leave a very wrong impression on the reader’s mind if we permitted him to suppose that the value of that work depends wholly on the ultimate justification of the theoretical views which it contains.  On the contrary, if they were disproved to-morrow, the book would still be the best of its kind—­the most compendious statement of well-sifted facts bearing on the doctrine of species that has ever appeared.  The chapters on Variation, on the Struggle for Existence, on Instinct, on Hybridism, on the Imperfection of the Geological Record, on Geographical Distribution, have not only no equals, but, so far as our knowledge goes, no competitors, within the range of biological literature.  And viewed as a whole, we do not believe that, since the publication of Von Baer’s Researches on Development, thirty years ago, any work has appeared calculated to exert so large an influence, not only on the future of Biology, but in extending the domination of Science over regions of thought into which she has, as yet, hardly penetrated.

FOOTNOTES: 

[61] On the Osteology of the Chimpanzees and Orangs:  Transactions of the Zoological Society, 1858.

[62] Colonel Humphreys’ statements are exceedingly explicit on this point:—­“When an Ancon ewe is impregnated by a common ram, the increase resembles wholly either the ewe or the ram.  The increase of the common ewe impregnated by an Ancon ram follows entirely the one or the other, without blending any of the distinguishing and essential peculiarities of both.  Frequent instances have happened where common ewes have had twins by Ancon rams, when one exhibited the complete marks and features of the ewe, the other of the ram.  The contrast has been rendered singularly striking, when one short-legged and one long-legged lamb, produced at a birth, have been seen sucking the dam at the same time.”—­Philosophical Transactions, 1813, Pt.  I., pp. 89, 90.

[63] Recent investigations tend to show that this statement is not strictly accurate.—­1870.