cially obtainable, it is deemed important enough to be reviewed here. An 

 additional reason is that it devotes considerable attention to the work of five 

 of Professor Seidel's former associates (Beier, Denker, Kirchner, Krauskopf, 

 Schwick) whose work was either not published so far, or pubhshed for the 

 greater part in German journals. 



After an introduction and a brief survey of the normal development of the 

 rabbit, the author takes up the following subjects in succession: the potencies 

 of the blastomeres and the developmental-physiological structure of the egg; 

 histochemical data relevant to embryonic regulation; electron-microscopical 

 studies on oocyte and blastomeres; proteins in the uterine secretion and in the 

 blastocyst; chemical feedback relationships between the egg and the genital 

 rystem (both directly and via the endocrine system). 



The review has summaries in German, English and French and is well 

 illustrated. The bibliography numbers close to one hundred titles. 



27 EXPERIMENTELLE BEITRAGE ZU EINER THEORIE 



DER ENTWICKLUNG 

 1968 (facsimile reprinting) 

 by H. Spemann Springer-Verlag 



296 pp. 217 figs. Berlin - Heidelberg - New York 



Price: DM 58.—; $ 16.— 



This is a facsimile offset reprinting of the classical work first published 

 in 1936. It is printed on heavy quality paper and attractively bound. The 

 original figures are of course included; most line drawings have come out well, 

 but the photographs and half-tone illustrations are less sharp than the original 

 ones. However, this was probably unavoidable if the original blocks were not 

 available. The publishers deserve our gratitude for re-issuing this important 

 and still miraculously topical book. 



28 GENETIC MOSAICS AND OTHER ESSAYS 



1968 

 by C. Stern Harvard University Press 



196 pp., 59 figs., 2 tbs. Cambridge, Mass. 



Price: 62 s. 



This book is based on three lectures given in 1965 at Harvard University 

 in the framework of the John M. Prather lectures. The book is named after 

 the second lecture, by far the longest of the three, and considerably enlarged 

 in its printed version. It is called "Genetic mosaics in animals and man", 

 numbers over 100 pages, and has a 13-page bibliography brought up-to-date 

 until 1966. It devotes considerable attention to such subjects as gynanders, 

 somatic crossing-over, mutational and chromosomal mosaicism, blood mosaic- 

 ism, intersexes, position effects, functional mosaicism, and dosage compensation 

 (the Lyon hypothesis). 



The other two lectures are a short essay placing the history of human 

 genetics in the perspective of Mendel's influence, and a very interesting and 

 well-written essay devoted largely to the work of Stern himself and his 

 associates on the developmental genetics of patterns in Drosophila. The latter 

 essay has been updated until 1967. 



A brief concluding section entitled "Thoughts on research" shows the author 

 in a more philosophical vein. 



The book is beautifully printed and illustrated, and is concluded by author 

 and subject indexes. 



24 



