370 Allgemeines. 



in a discussion of these views, should at all events be cogni- 

 sant of the advances made in the elucidation of the material 

 fabric and of the forces of nature. 



Dr. Merz' view being a wide one he has wisely chosen as 

 far as the sciences are concerned which deal with organic life, 

 to treat them as a whole and not to divide them into Botany, 

 Zoology and Paiaeontology respectively. For though conside- 

 rable progress has been made in the specialisation of the bio- 

 logical sciences during the past Century, yet when we come to 

 consider the main problems which they have attacked, we find 

 that the subjects which will stand out as having particulariy 

 occupied the thought of the Century, are just those which are 

 common to both botanical and zoological investigators. This is 

 true of the search after a rational (i. e. a natural) Classification 

 of living organisms, of the inquiry into the evolution of plants 

 and animals and of the investigations and speculations into the 

 mystery of life itself. Recognising the fundamental importance 

 of these problems, Dr. Merz has divided that part of the book 

 which deals with organic life into five chapters in which he 

 discusses: 



1. The morphoiogical view of nature, 



2. the genetic view of nature, 



3. the vitalistic view of nature, 



4. the psychophysical view of nature, 



5. the Statistical view of nature. 



The comprehensive treatment of the advances made during 

 a Century along each of these lines of thought shows the 

 breath of the authors reading, while one cannot fail to admire 

 his grasp of the technicalities of the subject and the judgment 

 he consequently displays in singling out the influences which 

 were constantly at work modifying and recasting the earlier 

 views. 



Nor can one be too grateful to the author for the profuse 

 references and the extensive extracts in the notes which accom- 

 pany the text, and which enable the reader to refer in any 

 particular matter to the authorities quoted in the text. 



In dealing with the morphoiogical view of nature, Dr. Merz 

 shows the revolution which has taken place during the past 

 Century in the Classification of plants and animals by the aban- 

 donment of the artificial Classification of Linnaeus in favour of 

 the natural Classification ofjussieu, DeCandoHe and of 

 more recent systematists. He also deals in this chapter, though 

 only in general terms with the advance of our knowledge in 

 the anatomy or internal morphology of plants as it might be 

 called. 



In the chapter on the genetic view of nature we have 

 practically an account of the rise of the Darwinian theory 

 of evolution from the earlier views of Lamarck and Goethe 

 as well as the summary of the post-Darwinian speculations of 

 Haeckel and Weisman. The work of de Vries 



