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From Nature (March 21, 1889) I take the second instance communicated by Mr. J. Jenner-Weir, who wrote as follows:–

“Mr. Marcus M. Hartog’s letter of March 6th, inserted in last week’s number (p. 462), is a very valuable contribution to the growing evidence that acquired characters may be inherited. I have long held the view that such is often the case, and I have myself observed several instances of the, at least I may say, apparent fact.

“Many years ago there was a very fine male of the Capra megaceros in the gardens of the Zoological Society. To restrain this animal from jumping over the fence of the enclosure in which he was confined, a long, and heavy chain was attached to the collar round his neck. He was constantly in the habit of taking this chain up by his horns and moving it from one side to another over his back; in doing this he threw his head very much back, his horns being placed in a line with the back. The habit had become quite chronic with him, and was very tiresome to look at. I was very much astonished to observe that his offspring inherited the habit, and although it was not necessary to attach a chain to their necks, I have often seen a young male throwing his horns over his back and shifting from side to side an imaginary chain. The action was exactly the same as that of his ancestor. The case of the kid of this goat appears to me to be parallel to that of child and parent given by Mr. Hartog. I think at the time I made this observation I informed Mr. Darwin of the fact by letter, and he did not accuse me of ‘flat Lamarckism.'”

To this letter there was no rejoinder. It may be said, of course, that the action of the offspring in each of these cases was due to accidental coincidence only. Anything can be said, but the question turns not on what an advocate can say, but on what a reasonably intelligent and disinterested jury will believe; granted they might be mistaken in accepting the foregoing stories, but the world of science, like that of commerce, is based on the faith or confidence, which both creates and sustains them. Indeed the universe itself is but the creature of faith, for assuredly we know of no other foundation. There is nothing so generally and reasonably accepted–not even our own continued identity–but questions may be raised about it that will shortly prove unanswerable. We cannot so test every sixpence given us in change as to be sure that we never take a bad one, and had better sometimes be cheated than reduce caution to an absurdity. Moreover, we have seen from the evidence given in my preceding article that the germ-cells issuing from a parent’s body can, and do, respond to profound impressions made on the somatic-cells. This being so, what impressions are more profound, what needs engage more assiduous attention than those connected with self-protection, the procuring of food, and the continuation of the species? If the mere anxiety connected with an ill-healing wound inflicted on but one generation is sometimes found to have so impressed the germ-cells that they hand down its scars to offspring, how much more shall not anxieties that have directed action of all kinds from birth till death, not in one generation only but in a longer series of generations than the mind can realise to itself, modify, and indeed control, the organisation of every species?

I see Professor S. H. Vines, in the article on Weismann’s theory referred to in my preceding article, says Mr. Darwin “held that it was not the sudden variations due to altered external conditions which become permanent, but those slowly produced by what he termed ‘the accumulative action of changed conditions of life.'” Nothing can be more soundly Lamarckian, and nothing should more conclusively show that, whatever else Mr. Darwin was, he was not a Charles-Darwinian; but what evidence other than inferential can from the nature of the case be adduced in support of this, as I believe, perfectly correct judgment? None know better than they who clamour for direct evidence that their master was right in taking the position assigned to him by Professor Vines, that they cannot reasonably look for it. With us, as with themselves, modification proceeds very gradually, and it violates our principles as much as their own to expect visible permanent progress, in any single generation, or indeed in any number of generations of wild species which we have yet had time to observe. Occasionally we can find such cases, as in that of Branchipus stagnalis, quoted by Mr. Wallace, or in that of the New Zealand Kea whose skin, I was assured by the late Sir Julius von Haast, has already been modified as a consequence of its change of food. Here we can show that in even a few generations structure is modified under changed conditions of existence, but as we believe these cases to occur comparatively rarely, so it is still more rarely that they occur when and where we can watch them. Nature is eminently conservative, and fixity of type, even under considerable change of conditions, is surely more important for the well-being of any species than an over-ready power of adaptation to, it may be, passing changes. There could be no steady progress if each generation were not mainly bound by the traditions of those that have gone before it. It is evolution and not incessant revolution that both parties are upholding; and this being so, rapid visible modification must be the exception, not the rule. I have quoted direct evidence adduced by competent observers, which is, I believe, sufficient to establish the fact that offspring can be and is sometimes modified by the acquired habits of a progenitor. I will now proceed to the still more, as it appears to me, cogent proof afforded by general considerations.