7 JULY 1923, Page 28

APPLIED SCIENCE.

Heredity in Poultry. By Professor R. C. Punnett, F.R.S. (Macmillan. 10s. net.) Heredity in Poultry. By Professor R. C. Punnett, F.R.S. (Macmillan. 10s. net.)

Professor Punnett has been studying inheritance in poultry since the early days of Mendelian investigation ; and the present book represents what is known on the subject from the Mendelian point of view. The fancier and the geneticist do not always see eye to eye ; and "practical men" on com- mittees have been known to distinguish between animal or plant breeding and Mendelism—to the disadvantage of the latter. However, the advantage of the scientific study of the matter—which in this case is the Mendelian one—is that what is ascertained is ascertained once and for all. There are ebviou.s gaps in the subjeetematter of this book—gaps which

are there chiefly because no one has yet done the work which could fill them. But the layman probably does not dream of the labour and time necessary to establish the facts that are known. Among the most interesting points are the dis- coveries concerning hen-feathered males and sex-linked characters ; while from a purely utilitarian point of view much has been done to build up on Mendelian lines strains pure for high egg-production. We would like to criticize Professor Punnett's method of presenting sex-linked inheritance, which is unnecessarily complex. He could have saved himself and his readers some trouble if he had adopted the chromosome hypothesis throughout. As a matter of fact, the word chromosome does not even occur in the index ! The National Poultry Institute is now beginning to take more interest in genetics, which should provide a welcome check to spine of the extravagances proposed by "the fancy." Professor Punnett's book will provide a welcome basis for future work, whether by professional biologist or fancier.