278 THE ZOOLOGIST. 



NOTICES OF NEW BOOKS. 



Problems of Nature: Researches and Discoveries of Gustav Jaeger, 

 M.ZX Edited and Translated by Henry G. Schlichter, 

 D.Sc. London : Williams & Norgate. 1897. 



This volume contains a selection made from numerous essays 

 published by Dr. Gustav Jaeger, who is well known to the 

 English-speaking world through his hygienic discoveries and 

 researches. To many it will come as a surprise that the familiar 

 name of the author is also attached to many original contribu- 

 tions on the subject of organic evolution, and that his work was 

 not only approved, but commended, by Darwin himself. The 

 contents of the present volume are divided into Part I. — Zoolo- 

 gical ; Part II. — Anthropological ; Part III. — Varia. In each 

 section zoologists will find much to interest them, though 

 probably our readers will be more attracted by the first part. 



Dr. Jaeger is an original thinker ; his views are enunciated 

 with much force and accentuated by brevity, whilst quotations 

 and foot-notes are phenomenally absent. He seizes his problem, 

 wrestles with it, and, it must be said, usually declares that 

 he has conquered it. Essays V. and VI., " On the Origin 

 of Species " and " Sexual Selection," though devoted to now 

 somewhat hackneyed subjects, are brimful of original suggestions 

 and fresh points for consideration ; in fact, it is quite a relief to 

 find a writer treating these topics by the Darwinian method and 

 yet from his own point of view. As regard sexual selection Dr. 

 Jaeger is one of the small coterie who are gradually acknow- 

 ledging the strength of this hypothesis — in fact, to use his own 

 words, he is " inclined to attribute considerably more importance 

 to sexual selection than Darwin does." Another most interesting 

 zoological essay is " On the Physiological Importance of Savo- 

 rous and Odorous Matters (matters which can be tasted and 

 smelled)." The author's " starting-point is that every animal 

 species has its specific odour." He also claims the same diversity 

 in taste, not only as regards the birds, but that the eggs of every 



