Phytohormones

Abstract

THIS book will prove very valuable as it reviews admirably a field in which the contributions have recently been so numerous that it is difficult to follow them all. (The authors give references to seventy-four papers on plant hormones for 1936 alone.) This rapid output is no doubt due to the discovery by Kögl and Koster-mans (Z. physiol. Chem., 235, 201) in 1934 that indole-3-acetic acid, sometimes called 'heteroauxin', a substance which can be synthesized, acts on plant growth in very nearly the same way as the natural growth-hormone or 'auxin': for this has provided wonderful opportunities for experimenting. But unfortunately, as the authors point out, the quality of some of this recent work has not been so good as that of the earlier work on the growth-hormone: indeed, some recent contributions have shown that the investigators responsible for them neither know what has been done already nor understand what are the problems at issue. The book should, therefore, be very useful, since it reviews critically the subject of the hormones of higher plants and shows up the main problems clearly: indeed it is one of the chief attractions of the book that it looks to the future as much as to the past. The authors include also summary statements of many interesting unpublished results, and although an excellent historical survey of the same field by Boysen Jensen entitled "Die Wuchsstofftheorie"appeared in 1935, progress has been so rapid that they have been able to include a great deal that was not in the earlier book.

Phytohormones

By F. W. Went Kenneth V. Thimann. (Experimental Biology Monographs.) Pp. xi+294. (New York: The Macmillan Co.) 17s. net.