The Biological Action of Growth Substances

different from that in the United States, this short volume, prepared for the lay reader, would be of considerable value to those infertile couples who wish to know more about their childlessness. Dr. Philipp has undertaken the always difficult problem of explaining a complex technical situation to readers unprepared by education or experience to absorb the implications of what he is trying to say. This is, of course, the curse of all "science writing," medical or otherwise, because the inevitable necessity for oversimplification unquestionably leaves the reader with a certain number of false impressions. If Dr. Philipp is correct in his figures, infertility in England is apparently greater than it is here, occurring there in one couple out of six whereas ten per cent of involuntary infertility is the figure usually quoted in this country. There is an interesting chapter somewhat reminiscent of Frazer's Golden Bough concerning the history and folk lore of infertility as well as a very straightforward account of sexual techniques as they are related to reproduction. I doubt very much if physicians in this country would consider either "over-keen-ness" or "excessive smoking" as a proven cause of infertility, or a "failure of the womb to grow fast enough" as being a cause of habitual abortion. These matters are somewhat incidental, however, and certainly do not detract from the value of the book. On the other hand, there is one comment which I hope will be corrected if the book goes to another edition, and that is the statement that 50 per cent of tubal plastic operations on the female are successful. This is a highly unrealistic and overoptimistic figure which is not borne out by facts either in this country or abroad. The bibliography is most unfortunate in its selection of American titles. Two of the volumes referred to are out of print, the name of one of the publishers is spelled wrong, and with one or possibly two exceptions the texts quoted are not considered authoritative in this country. It is also unfortunate that the illustrations are so amateurish technically and that the jacket and paper used in publishing the book is not more agreeable. The nineteen papers in this volume constitute a valuable survey of recent developments and approaches in the study of growth control by specific substances. As a botanist, this reviewer was more at home with the ten papers on plant growth, …