In the third it should show little or no sign of natural decrease for a very long time. In the fourth there may be absolute and total sterility, or sterility in regard to the particular organ, or a scar which shall show that the memory of the wound and of each step in the process of healing has been remembered; or there may be simply such disturbance in the reproduced organ as shall show a confused recollection of injury. There may be infinite gradations between the first and last of these possibilities. I think that the facts, as given by Mr. Darwin (“Plants and Animals,” &c., vol. i. pp. 466–472, ed. 1875), will bear out the above to the satisfaction of the reader. I can, however, only quote the following passage:— “ . . . Brown Séquard has bred during thirty years many thousand guinea-pigs, . . . nor has he ever seen a guinea-pig born without toes which was not the offspring of parents _which had gnawed off their own toes_, owing to the sciatic nerve having been divided. Of this fact thirteen instances were carefully recorded, and a greater number were seen; yet Brown Séquard speaks of such cases as among the rarer forms of inheritance. It is a still more interesting fact—‘that the sciatic nerve in the congenitally toeless animal has inherited the power of passing through _all the different morbid states_ which have occurred in one of its parents _from the time of division_ till after its reunion with the peripheric end. It is not therefore the power of simply performing an action which is inherited, but the power of performing a whole series of actions in a certain order.’” I feel inclined to say it is not merely the original wound that is remembered, but the whole process of cure which is now accordingly repeated. Brown Séquard concludes, as Mr. Darwin tells us, “that what is transmitted is the morbid state of the nervous system,” due to the operation performed on the parents. A little lower down Mr. Darwin writes that Professor Rolleston has given him two cases—“namely, of two men, one of whom had his knee, and the other his cheek, severely cut, and both had children born with exactly the same spot marked or scarred.”