ample, Professor Cope argues very ably that bones are lengthened by both stretch and impact, and that modifications thus produced are inherited. Even granting that this is true, how would it be possible for this process of lengthening to cease, since in active animals the stretch and impact must be continual? Professor Cope answers that the growth ceases when "equilibrium" is reached. I confess I can not understand this explanation, since the assumed stimulus to growth must be continual. But, granting again that growth may stop when an animal's legs become long enough to "satisfy its needs," how on this principle are we to account for the shortening of legs, as, for example, in the turnspit dog and the ancon sheep and numberless cases occurring in Nature? If any one species was able, by taking thought of mechanical stresses and strains, to add one cubit unto its stature, how could the same stresses and strains be invoked to decrease its stature?

These evidences are, I know, not the strongest ones which can be adduced in support of the Lamarckian factors. There are at present a relatively small number of such arguments which seem to be valid and the great force of which I fully admit. But the cases which I have cited are, I believe, fair samples of the majority of the evidences so far presented, and in the face of such "evidence" it is not surprising that one who is himself a profound student of the subject and a convinced Lamarckian prays that the Lamarckian theory may be delivered from its friends.*

6. Another line of evidence, and by far the most promising, is that of direct experiment. So far, most of the experiments which have been carried on to determine this question have been carried only halfway to a

* H. F. Osborn. Evolution and Heredity. Biological Lectures, 1890.

Value of direct experiment.

conclusion-they have shown that characters are acquired, they have usually failed to show that they are transmitted to descendants. Among animals one of the best-known cases is the inheritance of epilepsy and other disorders in guineapigs, due to certain nervous lesions of the parents. But Romanes,* who spent much time in trying to corroborate these results, concludes as follows: "On the whole, then, as regards Brown-Séquard's experiments, it will be seen that I have not been able to furnish any approach to a full corroboration."

Among plants, on the other hand, there is more and better experimental evidence, but it is not by any means as full or satisfactory as could be wished. Of one thing we may be certain-a satisfactory solution of the problem can be reached only by experiment. The mere observations and inductions of the morphologist, while affording valuable collateral evidence, can never furnish the crucial test. As long as we deal merely with probabilities of a low order there will be profound differences of opinion-e. g., Cope believes in all the Lamarckian factors; Romanes rejects use and disuse, but believes in the others; Weismann rejects all of them. Why? Is it because each does not know the facts upon which the others build? Certainly not. Those so-called facts are merely probabilities of a higher or lower order, and to one man they seem more important than to another. No conviction based even upon a high degree of probability can ever be reached in this way. There is here a deadlock of opinion, each challenging the other to produce indubitable proof. This can never be furnished. by observation alone. Possibly even experiment may fail in it, but at least it is the only hope.

*G. J. Romanes. Post-Darwinian Questions, 1895.

Return to the position of Darwin.

On the whole, then, I believe the facts which are at present at our disposal justify a return to the position of Darwin. Neither Weismannism nor Lamarckism alone can explain the causes of evolution. But Darwinism can explain those causes. Darwin endeavoured to show that variations, perhaps even adaptations, were the result of extrinsic factors acting upon the organism, and that these variations or adaptations were increased and improved by natural selection. This is, I believe, the only ground which is at present tenable, and it is but another testimony to the greatness of that man of men that, after exploring for a score of years all the ins and outs of pure selection and pure adaptation, men are now coming back to the position outlined and unswervingly maintained by him.

Finally, we ought not to suppose that we have already reached a satisfactory solution of the evolution

The final word

still far distant.

problem, or are, indeed, near such a solution. "We must not conceal from

ourselves the fact," says Roux, “that the causal investigation of organism is one of the most difficult, if not the most difficult, problem which the human intellect has attempted to solve, and that this investigation, like every causal science, can never reach completeness, since every new cause ascertained only gives rise to fresh questions concerning the cause of this cause."

V.

THE HEREDITY OF RICHARD ROE.

"Vom Vater hab' ich die Statur."*-Goethe.

WHEN Richard Roe was born, "the gate of gifts was closed" to him. Henceforth he must expect nothing new and must devote himself to the development of the heritage he had received from his father and mother.

Formation of character.

He must bring its discordant elements into some sort of harmony. He must form his Ego by the union of these elements. He must soften down their contradictions. He must train his elements of strength to be helpful to some one in some way, that others may be helpful

*"Stature from father and the mood

Stern views of life compelling;

From mother, I take the joyous heart
And the love of story-telling.

Great-grandsire's passion was the fair,

What if I still reveal it?

Great-granddam's, pomp and gold and show,

And in my bones I feel it.

"Of all the various elements

That make up this complexity,

What is there left when all is done,

To call originality?"

GOETHE: Zahme Xenien, vi; Bayard Taylor's translation in

part.

to him. He must give his weak powers exercise, so that their weakness shall not bring him disaster in the competition of life. For it is likely that somewhere, somehow, it will be proved that no chain is. stronger than its weakest link. Other powers not too weak, nor over strong, Richard Roe must perforce neglect, because in the hurry of life there is not time for every desirable thing. In these ways the character of Richard Roe's inheritance is steadily changing under his hands. As he grows older, one after another of the careers that might have been his, the men he might have been, vanish from his path forever. On the other hand, by steady usage a slender thread of capacity has so grown as to become like strong cordage. Thus Richard Roe learns anew the old parable of the talents. The power he hid in a napkin is taken away altogether, while that which is placed at usury is returned a hundredfold.

Now, for the purpose of this discussion, you, gentle reader, "who are an achievement of importance," or I, ungentle writer, concerning whom the less said the better, may be Richard Roe. So might any of your friends or acquaintances. So far as methods and principles are concerned, Richard Roe may be your lapdog or your favourite horse-or even your bête noire, if you cherish beasts of that character. Any beast will do. With Algernon Fitzclarence de Courcy or Clara Vere de Vere the case would be just the same. Let Richard Roe stand at present for the lay figure of heredity—or, if it seems best to you to humanize this discussion, let him be a man.

The man Richard Roe enters life with a series of qualities and tendencies granted him by heredity. Let us examine this series. Let us analyze the contents of this pack which he is to carry through life to the gates

Hereditary tendencies.

of the Golden City.