I cannot see the force of Mivart’s objection to the theory of production of the long neck of the giraffe (suggested in my first Essay), and which C. Wright seems to admit, while his “watch-tower” theory seems to me more difficult and unlikely as a means of origin.  The argument, “Why haven’t other allied animals been modified in the same way?” seems to me the weakest of the weak.  I must say also I do not see any great reason to complain of the “words” left out by Mivart, as they do not seem to me materially to affect the meaning.  Your expression, “and tends to depart in a slight degree,” I think hardly grammatical; a tendency to depart cannot very well be said to be in a slight degree; a departure can, but a tendency must be either a slight tendency or a strong tendency; the degree to which the departure may reach must depend on favourable or unfavourable causes in addition to the tendency itself.  Mivart’s words, “and tending to depart from the parental type,” seem to me quite unobjectionable as a paraphrase of yours, because the “tending” is kept in; and your own view undoubtedly is that the tendency may lead to an ultimate departure to any extent.  Mivart’s error is to suppose that your words favour the view of sudden departures, and I do not see that the expression he uses really favours his view a bit more than if he had quoted your exact words.  The expression of yours he relies upon is evidently “the whole organism seeming to have become plastic,” and he argues, no doubt erroneously, that having so become “plastic,” any amount or a larger amount of sudden variation in some direction is likely.

Mivart’s greatest error, the confounding “individual variations” with “minute or imperceptible variations,” is well exposed by C. Wright, and that part I should like to see reprinted; but I always thought you laid too much stress on the slowness of the action of Natural Selection owing to the smallness and rarity of favourable variations.  In your chapter on Natural Selection the expressions, “extremely slight modifications,” “every variation even the slightest,” “every grade of constitutional difference,” occur, and these have led to errors such as Mivart’s, I say all this because I feel sure that Mivart would be the last to intentionally misrepresent you, and he has told me that he was sorry the word “infinitesimal,” as applied to variations used by Natural Selection, got into his book, and that he would alter it, as no doubt he has done, in his second edition.

Some of Mivart’s strongest points—­the eye and ear, for instance—­are unnoticed in the review.  You will, of course, reply to these.  His statement of the “missing link” argument is also forcible, and has, I have no doubt, much weight with the public.  As to all his minor arguments, I feel with you that they leave Natural Selection stronger than ever, while the two or three main arguments do leave a lingering doubt in my mind of some fundamental organic law of development of which we have as yet no notion.