We hope that, if a second edition should appear, drastic changes will be 

 made in the composition of this atlas, which in its present form is quite un- 



^^^"^^^'°^^- P. D. NIEUWKOOP 



"LABORATORY STUDIES OF CHICK AND PIG EMBRYOS" 



1955 



by R. L. Watterson Offset print 



64 pp Burgess Publishing Company, Minneapolis 



Price: $ 2,25 



In this manual the anatomy of the 33, 48 and 72 hour chick embryo and of 

 the 10 mm pig embryo have been treated very accurately in a clear and easily 

 surveyable form. The development up to the first stage (approx, 12 — 15 

 somites) has been given in a separate chapter. Nevertheless it will be very 

 difficult for the beginner to understand the enormous step from the unincubated 

 egg up to the well organized embryo of 12 — 15 somites. In the 48 and 72 hour 

 embryos the general structure of the embryo probably does not change too 

 much to be understood by the student, but the topography of the various struc- 

 tures needs, in our opinion, much additional information. It is therefore sugges- 

 ted that at least one or two stages be inserted before the 33 hour embryo and 

 that some schematic drawings be added to illustrate the various morphogenetic 

 events taking place in between the successive stages to be studied. 



The presentation of only a single stage in the development of the pig might 

 be misleading for the students. Although many developmental processes are 

 comparable between the chick and the pig. the early development of the mam- 

 mal differs so deeply from that of the chick that, in our opinion, it cannot be 

 omitted entirely. 



The very thorough treatment of the stages given makes this laboratory 

 manual certainly of great value for the elementary student. We hope however 

 that the author will insert some further chapters in the next edition. 



P. D. NIEUWKOOP 



"THE ENERGETICS OF DEVELOPMENT. 



a Study of Metabolism in the Frog Egg" 



1954 



by L. G. Barth and L. J. Barth Columbia University Press, New York 



114 pp. with 17 figs in the text and Price: $ 3, — 



29 tabs 



This book is published by the Columbia University Press together with 

 several other samples of current scholarship, on the occasion of the 200^^ year 

 of Columbia's existence. 



As the authors state in the preface, our knowledge of the energetics of 

 development is at the present moment in a similar situation as morphological 



193 



