22 



concise form. The text has been clearly written and is nicely illustrated with a 

 hundred of illustrations. The physiological aspects of the reproduction process, 

 which are much more fragmentarily known than its morphological aspects, are 

 less comprehensively treated and cover only 1/7 of this work. We can highly 

 recommend this second edition to all people who like to get a general but 

 accurate survey of this interesting field of science, which enables them to find 

 their way to the e.xtensive literature published on these problems. It moreover 

 gives a very practical glossary with clear definitions of the terms used in this 

 booklet. 



P. D. NIEUWKOOP 



"GESCHLECHT UND GESCHLECHTSBESTIMMUNG IM TIER- 



UND PFLANZENREICH" 



Second Edition, 1951 



by M. Hartmann 



116 pp. with 61 illustrations 



and 7 tabs 



Sammlung Goschen Band 1127 



Walter de Gruyter & Co. 



Berlin 



pocket book size 



Price: DM 2.40 



This German pocketbook of the ,, Goschen Sammlung" deals with the pro- 

 blem of sex and sex-determination in plant and animal kingdom, in particular 

 with the many-sided aspects of bisexuality in the so called primary sexual 

 glands. The polymorphism of the secondary sexual glands will not be treated 

 in this booklet. The author discusses extensively the various types of sex- and 

 sex ratio determinations and the influence of the sex hormones upon them. 

 A general theory on sexuality is built up on the principle of bisexuality and the 

 genetically and a-genetically determined influences leading to the distinction of 

 six steps in sex determination. 



The clearly written and well organized text is illustrated with a large number 

 of good illustrations and diagrams. This booklet only contains a few references, 

 the majority of which is not very recent. Unfortunately the reader is not very 

 easily brought to the recent original literature on this subject on which so 

 much work is still going on. Also in this booklet one finds a very practical 

 glossary of the terms used. 



Just like the edition on reproduction it gives the reader a very accurate and 

 detailed but concise survey over a wide field of science. We will therefore 

 heartily recommend these cheap pocketbook editions which are within the 

 means of every scientist. 



P. D. NIEUWKOOP 



"TEXTBOOK OF HISTOLOGY" 



Sixth Edition, 1953 



by A. A. Maximov and W. Bloom W. B. Saunders Company 



616 pp. with 986 illustrations, Philadelphia and London 



257 in color, on 580 figs Price: $ 10.00 



This textbook on human histology has gradually received a very many sided 

 and comprehensive character in the successive editions by the various contri- 

 butions and suggestions of many well-known scientists. Nevertheless the author 



