This theory presupposes the complex structure of the germ plasm formulated by Weismann and rejected by various persons for various reasons. But granting Weismann the necessary structure of the germ plasm, can germinal selection accomplish what is claimed for it? I think not. Granting that variations occur about a mean, would not all the effects claimed for minus variations be counteracted by positive variations? Eye determinants, which, on account of their strength, secure more than their fair share of food, and thereby produce eyes that are as far above the mean as the others are below, and leave descendent determinants that are still stronger than their ancestry would balance the effect produced by weak-eye determinants. It is evident that a large, really extravagant development of the eye in such a fish as Chologaster would not effect the removal of the individual by personal selection; still less so in Amblyopsis, which not only lives in comparative abundance, but has lived for twenty months in confinement without visible food, and in which the eye is minute. It seems that all the admitted objections to degeneration by panmixia apply with equal force to germinal selection. This, however, would be changed were the effect of disuse admitted to affect the determinants, and this it seems Weismann has unconsciously admitted. So far we have considered germinal selection in the abstract only. All its suppositions are found to be but a house of cards when the actual conditions of degeneration are considered. We find that degeneration is not a horizontal process affecting all the parts of an organ alike, as Weismann presupposes, not even a process in the reverse order of phyletic development, but the more vital, most worked parts degenerate first with disuse and panmixia; the passive structures remain longest. The rate of degeneration is proportional to the past activity of the parts, and the statement that “passively functioning parts--that is, parts which are not alterable during the individual life by function--by the same laws also degenerate when they become useless” finds no basis in fact, and is an example of the inexact utterances abundant in the discussion of degeneration on which it is entirely unsafe to build lofty theoretical structures. As one example of the unequal degeneration we need only call attention to the scleral cartilages and the rest of the eye of Troglichthys rosæ.