354 SCIENCE PROGRESS 



last of these. The soft parts are also treated, and we have accounts of the forms 

 of cells, the internal structure of cells, etc. Again, in dealing with rate of growth 

 the date of publication did not allow of a reference to Donaldson's book on the 

 White Rat. 



One small point for criticism occurs, and that is the references to the 

 literature. In our opinion it would have been better to have given a bibliography at 

 the end of each chapter, as this facilitates the refinding of a reference only vaguely 

 remembered in reading the book. By no means the least interesting chapter of * 

 the book is the last, which deals with " The Theory of Transformations, or the 

 Comparison of Related Forms," in which the outlines of related organisms or of 

 skulls of related organisms are inscribed in systems of Cartesian co-ordinates with 

 most striking results. 



The modest claim in the Epilogue that " my task is finished if I have been 

 able to show that a certain mathematical aspect of morphology, to which as yet 

 the morphologist gives little heed, is interwoven with his problems, comple- 

 mentary to his descriptive task, and helpful, nay essential, to his proper study and 

 comprehension of Form " is fully substantiated. The author is to be congratulated 

 on a very interesting book that has an appeal for biologist and mathematician, and 

 in which both will find many suggestive hints for future work. 



C H. O'D. 



Genetics and Eugenics. By Prof. W. E. Castle. [Pp. vi + 353, with 132 

 figures and 37 tables.] (Harvard University Press ; London : Oxford 

 University Press, 1916. Price Ss. 6d. net.) 



This book is composed of three parts — the first on Genetics, the second on Eugenics, 

 and the third, in the form of an appendix, is a translation of Johann Mendel's 

 paper on plant hybridisation. The need for such a book was felt by the author, 

 who annually gave a course on these subjects to his pupils, and its aim is clearly 

 set out in the sub-title, " A Text-book for Students of Biology and a Reference 

 Book for Animal and Plant Breeders." It quite realises its object and is a source 

 for a great deal of useful information on the matters with which it deals, giving 

 in its extensive bibliography references to the most important works on the 

 subject. The addition of a number of photographs of the actual animals referred 

 to in the text brings home the salient features in a striking manner and adds 

 much to the appeal of the book. 



The part dealing with Genetics is a very plain, straightforward account of our 

 present-day knowledge in the subject prefaced by a short historical introduction. 

 The chapters on Eugenics are much shorter, mainly for the obvious reason that 

 our knowledge is much less extensive. On the whole the author is inclined to lay 

 too much stress on the Mendelian interpretation of inheritance, and tends to try 

 to fit the theory to the facts, even when its application is by no means obvious. 

 He does not go to the extremes sometimes encountered, and criticises very justly 

 the unreliability of the American data obtained by the Eugenics Record Office, 

 owing to the questionnaires being drawn up on the assumption that all characters 

 are inherited in Mendelian ratios. 



His conclusions with regard to the improvement of the human race will 

 probably meet with fairly general acceptance. Although we do not know enough 

 yet to manage human marriages as we do the mating on a stud farm, nor might it 

 ever be desirable from social and sentimental reasons to do so, yet we do know 

 enough to limit the propagation of the unfit. This whole question of the future of 

 the race is of paramount importance, and is particularly brought home at the 



