Reprinted from the BOTANICAL GAZETTE 53: 441-443, No. 5, May, 1912 



CURRENT LITERATURE 



BOOK REVIEWS 

 Heredity 



Several courses of public lectures on heredity have been made the basis 

 of a very readable book by CASTLE/ in which the principles of Mendelian 

 heredity and other related topics are discussed with special reference to their 

 bearing upon evolution and animal breeding. The rapidly increasing number of 

 expositions of Mendelism are warranted both by the growth of scientific 

 knowledge, and by the popular demand for information, and it is gratifying 

 to have the subject presented in easily comprehensible language by one who is 

 among the foremost investigators of the phenomena with which the book 

 deals. The manner of origin of this book makes it natural that the author 

 should illustrate the various principles of heredity by examples from his own 

 extensive experiments, whenever such examples are available, and this method 

 gives the book a unique value. 



The brief introductory chapter on "Genetics a new science" recognizes 

 the profound influence exercised by the theory of evolution in many fields of 

 human activity, and shows how the evolutionary idea has forced man to con- 

 sider his own probable future and to seek to control that future. As the 

 "existence of civilized man rests ultimately on his ability to produce from the 

 earth in sufficient abundance cultivated plants and domesticated animals," 

 "civilization may be advanced in a very direct and practical way" by 

 an increased knowledge of plant and animal breeding. To the solution 

 of the problem "how to create new and improved breeds better adapted 

 to the conditions of present-day agriculture," and especially to an exposi- 

 tion of the "operations" of Mendel's law of heredity, the author specifically 

 addresses himself. 



Chap, i on "the duality of inheritance" defines heredity as "organic 

 resemblance based on descent," and discusses fertilization, pointing out that 

 either eggs or sperms can under certain experimental conditions produce a 

 complete organism without union with another gamete, and that such a result 

 is realized regularly in nature in the case of male bees and wasps. The x and 

 2X generations of LOTSY are then considered under the designation N and 2N 

 generations, a change of terminology which has nothing to commend it. 

 Chap, ii distinguishes between "germ-plasm" and the body or "soma," and 

 cites experiments in the transplantation of eggs to afi alien soma as proof of 



1 CASTLE, W. E., Heredity in relation to evolution and animal breeding. 8vo, 

 pp. xii+i84. figs. 53. New York: D. Appleton & Co. 1911. 



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