Page:The Zoologist, 4th series, vol 5 (1901).djvu/461

Rh the knowledge to master the conception is not very large. These, however, are its high priests, and it would be well if the doctrine always came from them direct. Evolution is a revelation, but it is only made to those who diligently seek it, and the study of this Treatise on Zoology will greatly help those who care to make the quest.

aim of this brochure is clearly stated in the Preface—"The facts dealt with in the following pages are intended to show that the doctrine of the non-inheritance of acquired characters does not always hold good." To prove this negative is somewhat difficult; to even suggest it is to-day unpopular to those who believe en masse, and receive ex cathedrâ. As the author states—"All the various forms of mutilation of animals and man practised from time immemorial have failed hitherto to furnish cases of such mutilations being transmitted by descent." Mr. Kidd does not, however, suggest that such constant mutilations may have caused congenital variation which has become hereditary.

The author proposes a dynamical explanation for the presence of whorls, featherings, and crests in the hairy coats of mammals, and argues that, as a rule, they are due to the traction of the underlying muscles of the part in question, occurring in regions where opposing traction of underlying muscles is found; never occurring over the middle of a large muscle, and most uniform and strongly marked in animals with very strong muscles.

In considering the hair-slope in man, Mr. Kidd makes a distinct challenge to the followers of Weismann, which we only propose to record. It appears that, although the arrangement of hair in man corresponds to a considerable extent with that of the Anthropoid Apes, there are certain peculiarities, or an "exceptional type," in its distribution which raise the issue whether "the hair-slope in man is a strong argument against the theory of the Simian descent of Man (as far as present evidence goes), Zool. 4th ser. vol. V., November, 1901.