This book is the natural sequel of Social Origins and Primal Law, published three years ago. In Primal Law, Mr. J. J. Atkinson sought for the origin of marriage prohibitions in the social conditions of early man, as conceived of by Mr. Darwin. Man, in the opinion of the great naturalist, was a jealous animal; the sire, in each group, kept all his female mates to himself, expelling his adolescent male offspring. From this earliest and very drastic restriction, Mr. Atkinson, using the evidence of "avoidances" between kinsfolk in savage society, deduced the various prohibitions on sexual unions. His ingenious theory has been received with some favour, where it has been understood. This edition reproduced from a 1905 original.