“Even in the beginning I had dimly foreseen a point of contact between animal and vegetable grafts--a hyphen which my logically conducted labors made clear some time ago.... I will return to that. “When I took up animal grafting with enthusiasm, this branch of surgery was languishing. In fact, ever since the Hindoos of antiquity, who were the first grafters, it had remained stationary. “But perhaps you forget its underlying principles. That doesn’t matter. Learn them afresh. They are based, Nicolas, on this fact, that animal tissues possess, each of them, a personal vitality, and that the body of an animal is only the _milieu_ adapted to the life of those tissues--a _milieu_ from which they may be removed, and live for a more or less long time. “1. Don’t the nails and the hair grow after death? You are not ignorant of that. They survive. “2. A man who has been dead for fifty-four hours, and has left no descendants, still fulfills the chief condition for remedying that. Unfortunately, other essential faculties are wanting. But I will pass on. “3. In certain conditions of humidity, oxygenation and heat, scientists have been able to keep a rat’s tail, which had been cut off, alive for seven days; an amputated finger, for four hours. At the end of those periods they were dead, but if during those seven days or those four hours, they had been cleverly glued on again, they would have continued to live. “This is the procedure employed by the Hindoos, who thus restored to their places reintegrated noses that had been cut off by way of punishment, or if those appanages had been burnt, they replaced them by noses made of flesh and skin, taken, my dear Nicolas, from another part of the anatomy of the man who had been punished. “The operation thus effected goes into the first category of animal grafting, and consists in transplanting a part of the individual to himself. “The second consists of joining together two animals, by two wounds which coalesce. One can then cut off from first, the fragment of his person nearest the point of junction, which thereafter will live upon the second. “The third consists of transplanting, without any attachment, a part of one animal to another animal, always in such a way that it preserves its own life. That is the most elegant way of the three, and the one which has attracted me. “The operation was regarded as a ticklish one, for many reasons, the principal one of which is, that a grafting is less likely to succeed the further removed the two subjects are from one another in the scale of relationship. “Grafting succeeds when it is done on the same animal; less well from father to son, and worse and worse from brother to brother, from cousin to cousin, from Frenchman to Spaniard, man to woman, and child to old man. “When I came on the scene, the exchange I am talking about always came to naught in different zoölogical families, and more so still in the case of _genera_ and _species_.