I HAVE quoted in all ninety-seven passages, as near as I can make them, in which Mr. Darwin claimed the theory of descent, either expressly by speaking of “my theory” in such connection that the theory of descent ought to be, and, as the event has shown, was, understood as being intended, or by implication, as in the opening passages of the “Origin of Species,” in which he tells us how he had thought the matter out without acknowledging obligation of any kind to earlier writers. The original edition of the “Origin of Species” contained 490 pp., exclusive of index; a claim, therefore, more or less explicit, to the theory of descent was made on the average about once in every five pages throughout the book from end to end; the claims were most prominent in the most important parts, that is to say, at the beginning and end of the work, and this made them more effective than they are made even by their frequency. A more ubiquitous claim than this it would be hard to find in the case of any writer advancing a new theory; it is difficult, therefore, to understand how Mr. Grant Allen could have allowed himself to say that Mr. Darwin “laid no sort of claim to originality or proprietorship” in the theory of descent with modification. Nevertheless I have only found one place where Mr. Darwin pinned himself down beyond possibility of retreat, however ignominious, by using the words “my theory of descent with modification.” {202a} He often, as I have said, speaks of “my theory,” and then shortly afterwards of “descent with modification,” under such circumstances that no one who had not been brought up in the school of Mr. Gladstone could doubt that the two expressions referred to the same thing. He seems to have felt that he must be a poor wriggler if he could not wriggle out of this; give him any loophole, however small, and Mr. Darwin could trust himself to get out through it; but he did not like saying what left no loophole at all, and “my theory of descent with modification” closed all exits so firmly that it is surprising he should ever have allowed himself to use these words. As I have said, Mr. Darwin only used this direct categorical form of claim in one place; and even here, after it had stood through three editions, two of which had been largely altered, he could stand it no longer, and altered the “my” into “the” in 1866, with the fourth edition of the “Origin of Species.”