.'. 



327 



lungsg, >ehichte of Oscar Hertwig, will form a compendious account of 

 Embryology as it is understood to-day. 



Last in our series comes the Zoology 6 of Richard Hertwig, of which 

 the second and concluding portion is promised immediately. From 

 the reputation of the author and from the compact size of the volume 

 we had hoped for much in this work, but to us it seems far less satis- 

 factory than any of the other works enumerated. All of the others 

 bear a I tundant evidence of careful preparation hut this shows on every 

 page haste and carelessness. This shows itself not only in matter but 

 in typographic arrangement. Thus the chapter on the Development 

 of Systematic Zoology is made of equal rank to the section headed 

 " History of Zoology." On the textual side adverse criticism is easy. 

 Thus the account of the theory of evolution, though nearly thirty pages 

 in length, contains no mention of the post Darwinian labors. Ten 

 pages are devoted to the cell and cell division but no mention is made 

 of the part played by the centrosome. The account of coral forma- 

 tion (p. 210) is unintelligible and misleading. The Narcomedusaj 

 are ignored. A lack of proportion is everywhere noticeable. Thus 

 the Protozoa have 33 pages accorded them, while the Annelids have 

 but 12. These are but samples. The book, on the other hand has its 

 good features. We have been pleased with the concluding portions of 

 each section, entitled " Zusaramenfassung der Resultate," where in 

 categorical form the author has brought together in condensed shape 

 the most important facts regarding the group, and which might 

 almost be used for a syllabus of lectures. 



The text-books which have been mentioned are all in German, but 

 two of them are announced for English translation — Korschelt and 

 Heider's Embryology and that of Oscar Hertwig, while a portion of 

 Lang's Anatomy has already been issued. With this German zoologi- 

 cal vitality the English language offers nothing in comparison. No. 

 text-book has been issued from England or America in the last five 

 years and the long advertised zoology by an English zoologist will 

 hardly appear for five years to come. But Germany still puts out 

 new books and new editions. In the early future we are promised a 

 new Comparative Anatomy by Gegenbaur, new editions of both the 

 "Lehrbuch" and the "Grundriss" of Comparative Anatomy by 

 Wiedersheim, while Prof. Lang of Zurich is contemplating an 

 abridgement \ aatomy as soon as the larger work 



is complete. The proposed edition of Balfour's Comparative Embry- 



"Lehrbuch der Zoologie von Dr. Richard Hertwig, Erste Theil. Jena, 1891, 

 pp. 320. 



