The modern period of research with colchicine, we now learn, began in 1889, when Pernice described its action in causing metaphasic arrest. Its role as a mitotic poison was discovered in 1934 in Brussels in the laboratory of A. P. Dustin, whose son is one of the joint authors of this, the first book dedicated exclusively to the single substance colchicine and its effects. They of course first came into prominence in 1937 with the induction of poly-ploidy and since then there has been an ever-increasing flow of literature on the many and various properties of this fascinating drug. The authors have not attempted to catalogue all the contributions but rather to bring together and assess the most significant. The first chapter traces the knowledge of Colchicum from the time of the Ebers Papyrus of 1550 BC to the "eruption" in 1937, and includes a careful evaluation of the vexed question of priority in the discovery of the polyploidizing properties of colchicine. The phenomenon of metaphasic arrest or stathmocinesis is examined from the work of Dustin in 1924 onwards, then the effects on spindle and cytoplasm and on cell growth are discussed. Chapter 5 is devoted to the various plants that contain colchicine and the chemical aspect is dealt with in a special chapter by J. D. Loudon of Glasgow University. There follow chapters on pharmacology, on growth in animals and on cancer research and only in chapter 11 do we come to experimental polyploids; the various advantages of colchicine are expounded, terminology is explained, and an historical account of amphiploids leads to a discussion of their role in evolution and in agriculture, special consideration being devoted to the large body of literature dealing with the origin of bread wheat and the American cottons, and with the poly-ploid Nicotiana hybrids. Triploids are treated in the chapter on autoploids, where a bibliography of 237 references is provided but only isolated examples are dealt with in the text. After a chapter on aneuploids we come, rather surprisingly, to two short chapters devoted to criteria for judging polyploidy and techniques of colchicine treatment, in animals and plants respectively, and a final chapter on the mechanism of c-mitosis compares the action of colchicine with that of other spindle poisons. It is thought to be not merely by chance that colchicine has received such preponderant attention and on account of its unique structure and properties a long continuance of its preeminence is predicted. The book is provided with separate author and subject indexes. Bibliographers will no doubt quarrel with the practice in the former, and frequently also in the bibliographies at the end of each chapter, of citing authors with only their first initial. There is a certain lack of uniformity in the accentuation of the bibliographical references and some words, such as incompatibility and phytophthora, do not come through altogether unscathed in the text, where the author of the Origin of Species is moreover referred to as Sir Charles Darwin. On the whole, however, the standard of accuracy is relatively high for a book of this kind and the authors are to be thanked for undertaking the very difficult task of reviewing knowledge on a rapidly growing subject and for having attained such a large measure of success.