FIG. 7.--That lead poisoning can affect the germ plasm of rabbits is indicated by experiments conducted by Leon J. Cole at the University of Wisconsin. With reference to the above illustration, Professor Cole writes: "Each of the photographs shows two young from the same litter, in all cases the mother being a normal (nonpoisoned) albino. In each of the litters the white young is from an albino father which received the lead treatment, while the pigmented offspring is from a normal, homozygous, pigmented male. While these are, it is true, selected individuals, they represent what tend to be average, rather than extreme, conditions. The albino male was considerably larger than the pigmented male; nevertheless his young average distinctly smaller in size. Note also the brighter expression of the pigmented young."] There is, then, a suspicion that lead is a racial poison, but no evidence as yet as to whether the effect is permanent or in the nature of an induction. This concludes the short list of substances for which there has been any plausible case made out, as racial poisons. Gonorrhea, malaria, arsenic, tobacco, and numerous other substances have been mentioned from time to time, and even ardently contended by propagandists to be racial poisons, but in the case of none of them, so far as we know, is there any evidence to support the claim. And as has been shown, in the case of the three chief so-called racial poisons, alcohol, syphilis and lead, the evidence is not great. We are thus in a position to state that, from the eugenists' point of view, the _origination_ of degeneracy, by some direct action of the germ-plasm, is a contingency that hardly needs to be reckoned with. Even in case the evidence were much stronger than it is, the damage done may only be a physiological or chemical induction, the effects of which will wear off in a few generations; rather than a radical change in the hereditary constituents of the germ-plasm. The germ-plasm is so carefully isolated and guarded that it is almost impossible to injure it, except by treatment so severe as to kill it altogether; and the degeneracy with which eugenists are called on to deal is a degeneracy which is running along from generation to generation and which, when once stopped by the cessation of reproduction, is in little danger of being originated anew through some racial poison. Through these facts, the problem of race betterment is not only immensely simplified, but it is clearly shown to be more a matter for treatment by the biologist, acting through eugenics, than for the optimistic improver of the environment.