PREFACE TO THE FIRST EDITION. 
HAVING from my earliest years devoted myself, from taste, to the study 
of Comparative Anatomy; in other words, to the laws which preside over 
the organization of animals, and the modifications of that organization, as 
they are found throughout the diversified species—having, for nearly thirty 
years, consecrated to this science every moment which my duties left at 
my own disposal, I have ever kept in view, as the object of my labours, 
the resolution of the science into general laws, and into propositions of the 
simplest expression. My first essays soon made me perceive, that I could 
only attain this in proportion as the animals, whose structure I should 
have to elucidate, were arranged in conformity with that structure, so that 
in one single name of class, order, genus, &c. might be embraced all those 
species which, in their external as well as internal conformation, might 
have affinities either more general or particular. Now, this is what the 
greater number of naturalists of that epoch had never attempted, and what 
but few of them could have effected, had they even been willing to try, 
since a similar arrangement presupposes an extensive knowledge of the 
structures, of which it is partly the representation. 
It is true that Daubenton and Camper had supplied facts,—that Pallas 
had indicated views; but the ideas of these learned men had not yet exer~ 
cised upon their contemporaries the influence which they merited. The 
only general catalogue of animals then in existence, and the only one we 
possess even now, the system of Linneus, had just been disfigured by an 
unfortunate editor, who did not even take the pains to examine the prin- 
ciples of that ingenious methodist, and who, wherever he found any dis- 
order, seems to have tried to render it more inextricable. 
It is no less true, that, upon particular classes, there existed some very 
extensive works, which described a considerable number of new species; 
but then the authors of these performances scarcely carried their attention 
beyond the external relations of these species, and no one was found to 
employ himself in arranging the classes and orders according to the nature 
of the structure of the animals. 
I was compelled then,—and the task occupied a considerable period of 
time,—to make anatomy and zoology, dissections and classification, the 
pioneers of my steps; to search for better principles of distribution in my 
VOL. I. c 
