534 



SCIENCE 



[N. S. Vol. XLI. No. 1058 



sage of the modern educational world and that 

 he would be recreant to his sense of truth if 

 he held his peace. Geaham Lusk 



LETTER FROM PROFESSOR ED. OLAPAEEDE 



J'apprends de divers cotes que " Science " 

 a reproduit une nouvelle d'apres laquelle 

 j'aurais du demissionner de mes fonctions a 

 rUniversite de Geneve. Cette nouvelle est 

 entierement inexacte. La presse allemande, 

 qui I'a d'abord propagee, m'a confondu avec un 

 de mes cousins, professeur de droit germanique 

 a Geneve; celui-ci a en effet ete suspendu 

 provisoirement de son enseignement pour avoir, 

 dans son cours, reproche a la population 

 civile JDelge d'avoir tire sur ses agresseurs alle- 

 mands. 



Au moment ou ces incidents se sont produits, 

 j'etais mobilise, a la frontiere, comme medecin 

 d'un bataillon de montagne. J'y suis done 

 entierement etranger. Mais, puisque mon nom 

 a ete prononce, permettez-moi d'ajouter, pour 

 eviter tout malentendu, que je ne partage 

 aueunement la maniere de voir de mon cousin, 

 dont la mere est allemande, et qui a ete lui- 

 meme eleve en Allemagne, ce qui explique 

 suffisamment son manque d'objeetivite en 

 cette affaire. Ed. Clapaeede 



Fagult]!; des Sciences de Geneve 



SCIENTIFIC BOOKS 

 Text-iooh of Embryology. Vol. I. Inverte- 



brata. By E. W. MaoBride, M.A., D.Sc, 



LL.D., F.E.S. London, Macmillan & Co. 



1914. Pp. 692. 



" The design of this text-book of embryol- 

 ogy of which this is the first volume, is to as- 

 sociate the structural development of embryos 

 with broad generalizations of what is known 

 of their physiology. Attention will be drawn, 

 for instance, to the correlation between the 

 function of certain organs of a larva and its 

 habit of life, and, in a more general way, be- 

 tween function and habit and the course of 

 development. Eeference will he made to some 

 of the more striking results obtained by ex- 

 perimental embryological research. Attention 

 will be drawn to gaps in our knowledge which 

 indicate promising fields for research." 



These words by the editor, Professor Walter 



Heape, introduce a work which promises to be 

 as useful to the embryologist as is the Cam- 

 bridge Natural History to the zoologist. Two 

 other volumes are to be included in the work, 

 one on the "Lower Vertebrata" by Professor 

 John Graham Kerr and one on the mammals 

 by Mr. Eichard Assheton, both announced to 

 be in press. 



The volume before us measures 692 pages 

 and is illustrated by 468 well-executed figures. 

 The treatment is necessarily very succinct, as 

 will be apparent when we consider that Bal- 

 four's treatment of invertebrata in his " Com- 

 parative Embryology" of 1885 was almost 

 equally extended, and that Korschelt and 

 Heider devoted 1,509 pages to the same 

 groups in 1890-93. Professor MacBride's 

 treatment, of course, includes later investiga- 

 tions also. In each phylum at least one tjrpe 

 is selected for detailed description of the en- 

 tire life history, and in the larger phyla each 

 class may be so represented. Comparative 

 data are then discussed; the experimental 

 embryology is then treated, in some groups at 

 least; and in conclusion the phylogeny of the 

 phylum is considered from the point of view 

 of the developmental history. This method 

 admits both of considerable detail in the treat- 

 ment of the type forms, and also of succinct- 

 ness in the consideration of the comparative 

 data. It avoids the vicious habit of construct- 

 ing life histories from pieces of different 

 ontogenies, and at the same time preserves 

 some advantages of the comparative method. 



The descriptive part of Professor Mac- 

 Bride's book is well done, and will be most 

 useful. Special note should be made of the 

 adequate descriptive treatment of cell-lineage 

 hitherto lacking in text-book form. A se- 

 lected list of literature follows each chapter, 

 and the index appears to be very full. The 

 practical embryologist will find methods of 

 study in many places. 



In such a book very much depends on the 

 point of view of the author. The material is 

 so great that rigid selection has to be prac- 

 tised : what is to be rejected, what retained and 

 what principles are to be emphasized? There 

 is no doubt about the point of view of Pro- 



