[Footnote 3: The present conditions that obtain with regard to the celebration of marriages are very prone to have a certain amount of intoxication as their result. Perhaps, then, it is a fortunate thing, as has often been said, that the first child is not born until some considerable time after it might normally be expected. It has been said more than once, however, that first children are a little more likely to have certain degenerative defects than are others, and a connection has been found between certain abuses of stimulants and incidental exhaustion to account for this. One of the most amusing things to Li Hung Chang, on his travels through our country, was the curious publicity we give to everything connected with marriage, while presumably our Christian ideas should rather counsel a veiling of the mysteries, religious and physical, connected with it. Certain it is that the present tendency towards farewell dinners at clubs, and other festivities of various kinds, are not at all likely to result in benefit to the presumably hoped-for offspring.] The only real light that has been thrown on the puzzling details of heredity has come from work in the same field in which Mendel made his ground-breaking observations. {127} De Vries, the professor of botany at the University of Amsterdam, has succeeded in showing that new species of plants may be made to arise by careful attention to certain anomalous plants which occur from generation to generation. These plants breed true, that is, maintain their own peculiarities. To begin with, they are quite different from the parent plants, and the difference is perpetuated by inbreeding. So far the problem of the origin of species has been supposed to depend upon the normal variation that is noticed in plants and animals. All living things differ from one another, even though they may belong to the same species, and differ sometimes in remarkable degrees. This continuous variation was supposed to account for the origin of new species when it became excessive. It has become well recognised now, however, that such differences gradually disappear in the course of the normal multiplication of plants and animals. The tendency is much more towards the disappearance than the maintenance of peculiarities. There are certain discontinuous variations, however--sports, as they are called--in plants which differ very markedly in some quality from others, and these have the tendency to perpetuate themselves. Just why these sports occur is not known, nor how. They occur in a certain small percentage of all normal plants, but may die out, though it takes but little encouragement to succeed in helping them to maintain themselves. It is this that De Vries has done, and thus has succeeded in raising what would be called new species of plants.