drawings. The labeling is clear, but the alphabetical lettering system used is 

 definitely inferior to a self-explanatory system. The representation of the position 

 of the mammary ridges in fig. 31 is wrong. There is a small error in fig. 60, where 

 the special visceral efferent column is denoted as afferent. In fig. 67 it is not 

 clear why the mature eye is shown in pear-shape (fixation shrinkage?). 



For some reason the subject of twins is not mentioned. Double monsters and 

 teratomas are likewise not discussed. The book is concluded by a subject index. 



14 LABORATORY EMBRYOLOGY OF THE FROG 



1968 



By L. E. Downs Wm. C. Brown Comp. 



51 pp., 13 figs. Dubuque, Iowa 



(paper-bound) Price: $ 2.25 



This laboratory manual is of the conventional type. It contains 15 exercises 

 based on serial sections and cleared whole mounts of the frog embryo. The first 

 deals with cleavage, blastula, and gastrula, the second with neural plate, neural 

 groove, and neural tube stages. Then follow three excercises on the four milli- 

 meter, four on the six millimeter, two on the eight millimeter, and two on the ten 

 millimeter stage. Each exercise is concluded by a list of questions. 



The manual is illustrated with very good drawings of serial sections and whole 

 mounts. The serial section drawings are often accompanied by "exploded" 

 perspective drawings of the whole embryo, showing three-dimensional relation- 

 ships. 



There are a number of annoying printing errors in the titles of the first three 

 exercises. 



1 5 EVOLUTIONARE ONTOGENIE DER TIERE 



1966 



By G. A. Schmidt Akademie-Verlag 



364 pp., 108 figs., 14 tbs. Berlin 



(Edited by H. G. Herbst) Price: MDN 36.— 



This textbook is a translation based on a revised version (1964) of the author's 

 "Animal embryology", first published in Russian in 1951. The proper English 

 equivalent of the title would be "Comparative and evolutionary animal embryo- 

 logy". The author has been active in the field of comparative and experimental 

 embryology for more than forty years. 



The book was written primarily for biology students. It is based on data from 

 three major disciplines, viz. comparative embryology and ontogeny, experimental 

 embryology (Entwicklungsmechanik), and the more recent discipline of oecolog- 

 ical embryology, to which the author himself and a number of his Russian 

 colleagues have contributed greatly. The whole field of evolutionary embryology 

 is strongly linked up with two nineteenth-century Russian investigators: 

 A. Kowalewski and I. Metschnikow, and their numerous followers. Naturally, 

 in this book much stress is placed on the contributions of Russian workers, and it 

 is this feature that makes it particularly interesting for those who are unable to 

 read the original Russian literature. 



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