THE 



AUTHOR'S PREFACES. 



PEEFACE TO THE FIRST EDITION. 



Having been devoted, from my earliest youth, to the study of comparative anatomy, 

 that is to say of the laws of the organization of animals, and of the modifications 

 which this organization undergoes in the various species, and having, for nearly thirty 

 years past, consecrated to that science every moment of which my duties allowed me 

 to dispose, the constant aim of my labours has been to reduce it to general rules, and 

 to propositions that should contain their most simple expression. My first essays soon led 

 me to perceive that I could only attain this object in proportion as the animals, whose 

 structure I should have to elucidate, were arranged in conformity with that structure, 

 so that under one single name, of class, order, genus, &c., might be embraced all those 

 species which, in their internal as well as exterior conformation, present accordancies 

 either more general or more particular. Now this is what the greater number of 

 naturalists of that epoch had never sought to effect, and what but few of them could 

 have achieved, even had they been willing to try ; since a parallel arrangement presup- 

 poses a very extensive knowledge of the structures, of which it ought, in some measure, 

 to be the representation. 



It is true that Daubenton and Camper had supplied facts, — that Pallas had indicated 

 views ; but the ideas of these well-informed men had not yet exercised 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 

 Linnaeus, — had just been disfigured by an unfortunate editor, who did not so much as 

 take the trouble to comprehend the principles of that ingenious classifier, and who, 

 wherever he found any disorder, seems to have tried to render it more inextricable. 



It is also true that there were very extensive works upon particular classes, which 

 had made known a vast number of new species ; but their authors barely con- 

 sidered the external relations of those species, and no one had employed himself 

 in co-arranging the classes and orders according to their entire structure : the cha- 

 racters of several classes remained false or incomplete, even in justly celebrated 

 anatomical works ; some of the orders were arbitrary ; and in scarcely any of these 

 divisions were the genera approximated conformably to nature. 



