The Psychiatrist, His Training and Development

are in general excellent, and the printed discussion is both informative and interesting. This volume reviews the field very well and indicates aspects of the field in which there is diversity of opinion. This volume is mainly concerned with problems of bacterial adaptation and considers many different aspects, including the problems of genetic and non-genetic factors in adaptation, enzymatic adaptation, and drug resistance. However, certain aspects of adaptation in protozoa and fungi are also considered. Enzymatic adaptation is perhaps the most thoroughly discussed aspect of adaptation, with a group of fine papers by S. Spiegelman, H. A. Halvorsen, M. Cohn, J. Monod, M. R. Pollack, P. P. Slonimski, and R. Knox. These papers, together with the discussions, cover the known facts of the field and go on to add a good deal of interesting speculation on the induction process. The many problems of drug and antibiotic resistance are covered in a series of papers by E. P. Abraham, Mary Barber, D. A. Mitchison, and L. F. Hewitt. Adaptations in Paramecium are discussed by G. H. Beale, in fungi by W. Brown and R. K. S. Wood, and in thermophiles by L. F. L. Clegg and S. E. Jacobs. The influence of bacteriophage on bacterial variation and evolution is considered in a fine paper by L. F. Hewitt. Throughout the volume, the controversy over genetic factors versus nongenetic factors in adaptation plays a prominent r6le. Two papers, one by Sir Cyril Hinshelwood and the second by A. W. Ravin, specifically consider this problem. There can be no doubt that gene mutation and selection account for a majority of adaptations of the drug resistance type. The possibility of other types of adaptation, however, is widely discussed. The general discussion of this problem is well done and clarifies many of the problems that confront workers in this field. The volume is well printed and well edited and is heartily recommended to anyone interested in the problems of microbial adaptation.