TABLE OF CONTENTS 



PAOB 



Introbuction xvii 



Life — The Philosophie Zoologique — Zoology — Evolution — In- 

 heritance of acquired characters — Classification — Physiology — 

 Psychology — Conclusion. 



Peeface 1 



Object of the work, and general observations on the subjects 

 dealt with in it. 



Preliminary Discourse 9 



Some general considerations on the interest of the study of 

 animals and their organisation, especially among the most 

 imperfect. 



PART I. 



CONSIDERATIONS ON THE NATURAL HISTORY OF ANIMALS, THEIR 

 CHARACTERS, AFFINITIES, ORGANISATION, CLASSIFICATION 

 AND SPECIES. 



cflis, 



^ I. ]0n Artificial Devices in dealing with the Pro- 

 ""^-"^ DUCTioNs OF Nature - - - - - 19 



How schematic classifications, classes, orders, families, genera 

 and nomenclature are only artificial devices. 



Il\ Importance op the Consideration of Affinities - 29 



How a knowledge of the affinities between the known natural 

 productions hes at the base of natural science, and is the funda- 

 mental factor in a general classification of animals. 



III. Of Species among Living Bodies, and the Idea that 



we should attach to that word - - - ''35 

 That it is not true that Species are as old as Nature, and have 

 all been in existence for an equal period ; but that it is true that 

 they have been formed one after another, that they have only a rela- 

 tive constancy, and are only invariable temporarily. 



