The natural selection of favoured variations would not amount to much, were the variations not perpetuated by transmission to the young which they produce. This, it is common knowledge [see (3)], does take place. It is known also that a variation so established is as a result of the regular process of variation presented in larger volume or emphasised in character in some individuals of subsequent generations, and by continued “natural selection” it may become more and more a prominent or dominant feature of the race. So far, the only assumption made by Mr. Darwin is that any or some of the endless variations which occur in all the offspring of wild plants and animals, in various combinations and degree in each individual, can be sufficiently important to determine the survival or non-survival of the organisms possessing them. That is a matter which has been largely studied and discussed. The verdict of those who have studied on the spot (as Darwin himself did) the teeming life of the tropics, the insects, birds, and plants of those regions, is that we are justified in considering that small variations are sufficiently important to turn the scale in favour of survival or non-survival. It is not easy for a man who is not a determined naturalist, constantly observing the ways of wild living things, to appreciate the evidence as to the efficacy of small variations, even were I able here to submit it to him. It is to be found in the published works of an army of investigators. In any case it is granted that effective variations—whether small or great—occur in nature, and that natural selection favours and perpetuates the new and fitter variety to the exclusion of the less fit.