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Textbook. of Genetics. BY WILLIAM HOVANITZ. Houston, New York : Elsevier Press, Inc. ; London: Cleaver Hume Press. 1953. 420 pp., 49 tables, 266 photographs and diagrams. 42s. 6d.

While students are obliged to write examination papers, it is difficult to see why, in the presence of several perfectly good text-books on genetics, so many new professors feel obliged to write yet another one; exciting the attitude of an examiner rather than that of a reviewer, some of these books have not come up to expectation. It would be going too far to apply this sentiment to Prof. Hovanitz’s book, but it is regrettably impossible to overlook the many defects which even a casual glance reveals.

The author’s aim a t comprehensiveness and modernity appears only partially matched by the range of his knowledge and reading, which results in a very uneven treatment of the various aspects of genetics. Cytology and the statistical approach to genetics are adequately discussed, the description of breeding methods for the improvement of plants and animals-though brief- is useful and genetical changes in population are aptly illustrated by the author’s own excellent work on American butterflies. Less well covered are microbial and developmental genetics. The author rightly stresses the relative paucity of our present knowledge in human genetics, but all the same a great deal more-and in other respects a great deal less-is known than one might gather from his book. The linkage map for man (p. 151), for example, is perhaps per- missible as far as the sex chromosomes are concerned, but in respect of the autosomes it could be described as pure phantasy, if several precedents only slightly less audacious did not exist. To say the least, to present such a map in the same manner as the well-documented linkage maps for Drosophila, Zeu, Mus and NeurospoTa is highly misleading. On the other hand, too little use is made of the vast and in parts excellent information available in the medical literature on clinical genetics. Less serious but quite irritating are the many errors in detail and misprints, only four of which are mentioned in the errata. Here are a few examples: In the caption of Fig. 12 the probability in the explanatory example equals 0.017 and not 0.17 as stated. In the caption for Fig. 86 chromatid must be read for chromatin. On p. 153 it is stated that ‘no sex- linked genes have ever been discovered in the house mouse ’, while a t least two such genes have been described a year ago. On p. 309 ultra-violet light is described as a ‘non-ionizing radiation ’.

There is a welter of tabulation, some of which will be greatly a,ppreciated, but there are in the opinion of the reviewer quite a few unnecessary illustrations ; for instance, the costly colour plates illustrating mammalian fur colour are neither beautiful nor useful, and the purpose of Fig. 260 is not easily perceived. It is a picture of diabetic twin sisters who, it is stated, cannot taste phenylthiourea, while the other members of their family are healthy and can taste this substance. The caption says : ‘ The case is consistent with the association between diabetes and taste blindness to P.T.C. in human populations.’ While this statement cannot be contradicted, one wonders how a double portrait of two apparently identical twins can possibly illustrate an association between two traits, neither of which can be seen in the picture, and which, according to the newest published literature, is dubious to say the least.

It might well be that the blame for many of the errors in detail rests with the publishers and not with the author. As it is, mature geneticists may find their uses for the book. They are unlikely to acknowledge its merits and less likely to recommend it to their students.

H. KALMVTS

The Design and Analysis of Experiment. By M. H. QUENOUILLE. London: Charles Griffin and

The author of this book clearly has considerable experience in t,he design of statistical experi- ments and familiarity with the literature. The publishers have filled an important gap in their coverage of statistics. The book is intended to be expository rather than original, and i t is suitable as a text-book of intermediate standard, especially as a supplement to a cnurse of

Co., Ltd. 1953. Pp. xiii+356. 36s. net.