The attitude of Mr. Darwin’s mind, whatever it may have been in regard to the theory of descent with modification generally, goes so far to explain his attitude in respect to the theory of natural selection (which, it cannot be too often repeated, is only one of the conditions of existence advanced as the main means of modification by the earlier evolutionists), that it is worth while to settle the question once for all whether Mr. Darwin did or did not believe himself justified in claiming the theory of descent as an original discovery of his own. This will be a task of some little length, and may perhaps try the reader’s patience, as it assuredly tried mine; if, however, he will read the two following chapters, he will probably be able to make up his mind upon much that will otherwise, if he thinks about it at all, continue to puzzle him. Chapter XIII Darwin’s Claim to Descent with Modification MR. ALLEN, in his “Charles Darwin,” {168a} says that “in the public mind Mr. Darwin is commonly regarded as the discoverer and founder of the evolution hypothesis,” and on p. 177 he says that to most men Darwinism and evolution mean one and the same thing. Mr. Allen declares misconception on this matter to be “so extremely general” as to be “almost universal;” this is more true than creditable to Mr. Darwin. Mr. Allen says {168b} that though Mr. Darwin gained “far wider general acceptance” for both the doctrine of descent in general, and for that of the descent of man from a simious or semi-simious ancestor in particular, “he laid no sort of claim to originality or proprietorship in either theory.” This is not the case. No one can claim a theory more frequently and more effectually than Mr. Darwin claimed descent with modification, nor, as I have already said, is it likely that the misconception of which Mr. Allen complains would be general, if he had not so claimed it. The “Origin of Species” begins:— “When on board H.M.S. _Beagle_, as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relation of the present to the past inhabitants of that continent. These facts seemed to me to throw some light on the origin of species—that mystery of mysteries, as it has been called by one of our greatest philosophers. On my return home it occurred to me, in 1837, that something might perhaps be made out on this question by patiently accumulating and reflecting upon all sorts of facts which could possibly have any bearing on it. After five years’ work I allowed myself to speculate upon the subject, and drew up some short notes; these I enlarged in 1844 {169a} into a sketch of the conclusions which then seemed to me probable. From that period to the present day I have steadily pursued the same object. I hope I may be excused these personal details, as I give them to show that I have not been hasty in coming to a decision.”