Principles of Animal Virology

other intellectual, in our population are discussed, and a possible resolution to the conflict is suggested. There are some details of this book whose lack of accuracy might disturb the specialized reader, and this reviewer, who is an obstetrician and gyne-cologist, only hopes that those areas in which he is less informed are more accurate than the sections dealing with aspects of his specialty. It is regrettable , for instance, that the author did not either seek adequate gynecologi-cal consultation or submit his manuscript to the clinical perusal of a qualified endocrine gynecologist before publication, because a number of inexact statements in the realm of this specialty could easily have been corrected. We know of no responsible urologist, for example, who has reported fifty per cent success in doing a reanastomosis in the vasectomized male, nor do we know of any satisfactory gynecological experience with the use of the cornual cautery for purposes of sterilization in the female. The fact that it is "as yet not widely used" is not because gynecologists are generally not familiar with it but simply because it has been tried and found wanting. The statement that fifty per cent of cases of infertility are correctable seems to us unduly optimistic, and it would have been of considerable interest in connection with the discussion of various techniques of sterilization to discuss the laws refusing permission for sterilization in many states in this country. The reviewer, however, does not wish to be captious in his criticism of these and other minor inaccuracies, because the overall picture presents a point of view which is badly needed in our understanding of present-day population problems. Possibly the author is most capable when he discusses the more theoretical aspects of the problem, especially those concerning desirable population management. Certainly the "welfare-optimum" concept is a most useful one, and we feel that the expression "teleo genesis" and the title, Adaptive Human Fertility, are most fortunate ones and will rapidly become familiar terms in the specialized language of the demographer. In addition to being a text, Dr. Burnet's latest book is a joy to read. Not many scientific writers have the ability to say simply and directly what they mean to say. Dr. Burnet does. Not many scientists have the courage to say what they think without the crutches of their own or others' experimental results. Dr. Burnet does. And in so doing, …