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19 for it. And it is doubtful whether the new theory of "organic selection" will all the difficulties. The most recent of Weismann's theories, namely that which he calls "general selection" is an attempt in to  th difficulty and also to account for variations occurring in determinate directions. But we here enter the regions of pure speculation and it is therefore impossible to prove or disprove an hypothesis of this sort.

Another line of argument advanced by Spencer (Appendix to the, Vol.1) and one which Weismann and his followers have failed to meet satisfactorily, is that derived from experiments on the sense of touch. The unlikeness of tactual discriminativeness displayed by different parts of the body-surface can be expressed by actual measurements. It is very difficult to explain by natural selection how such a distribution of tactual perceptiveness as is found can have arisen. But if the effects of use are inherited, the facts can be readily accounted for: it is well known from observations made on the blind the constant exericseexercise [sic] of the tactual nervous structures leads to their further development. The same result is well shown in the fingers of compositors.

A case which has been considered by Weismann to afford a very good test is that of the progressive degradation of the human little toe. This had been ascribed by some of those who hold Lamarckian views to the of  constant boot-pressure. Weismann was able without much difficulty to overthrow this argument. For a