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NOTICES OF NEW BOOKS. 



The Analysis of Racial Descent in Animals. By Thos. H. Mont- 

 gomery, Jr., Prof. Zool. University, Texas. New York : 

 Henry Holt & Co. 



The argument throughout this book is largely a phylogenetic 

 one, as distinctly avowed by the author in his preface, and 

 requires careful study, many of the conclusions arrived at being 

 based on facts relating to lowly organized animals which are not 

 much noticed in these pages, and therefore somewhat outside the 

 special purview of our readers. Those, however, who do not give 

 the special attention necessary to appreciate its main thesis will 

 find very much to both interest and instruct in more familiar 

 biological subjects, and this remark particularly applies to the 

 first chapter, which is devoted to "Environmental Modes of Exist- 

 ence." Zoological science marches on with giant strides ; most of 

 us in our own lifetimes have seen the rise and culmination of the 

 geographical side in the study of the distribution of animals ; but 

 a new method based on another consideration has arisen, and, as 

 Prof. Montgomery observes, " It is now a question of environ- 

 mental distribution, not geographical." Haeckel, for the three 

 main divisions of animal life — terrestrial, fresh-water, and marine 

 — has proposed the terms geobios, limnobios, and halobios, while 

 Prof. Montgomery now adds — and with good reason — two more 

 to the list. For animals like a Mosquito or Toad, which live 

 during a particular period in one medium, and later in their 

 lives migrate into a different medium, he gives the differential 

 name diplobios ; and for others which at some period of their 

 existence live as internal parasites he proposes the environ- 

 mental term entobios. For a philosophical conception of the 

 distribution of animals, it is as necessary to remember these as 

 well as the more familiar zoo -geographical regions, and it 

 becomes every day more apparent, especially in zoology, that 

 every scientific worker is but a pioneer, and every theory but a 

 suggestion. The observational or bionomic method, on which the 



