PREFACE TO THE SECOND EDITION. 
THE preceding preface exhibits a faithful account of the 
state in which I found the history of animals at the time the 
first edition of this work was published. During the twelve 
years that have since elapsed, this science has made immense 
progress. The labours of numerous, courageous, and learned 
travellers, who have explored every region of the globe, the 
rich collections formed and rendered public by various go- 
vernments, the profound and splendid works where new 
species are described and figured, and whose authors have 
been determined to detect their mutual relations and to con- 
sider them in every light(1), have all been instrumental in 
producing this result. 
I have endeavoured to avail myself of these discoveries, as 
far as my plan permitted, by first studying the innumerable 
specimens received at the Cabinet du Roi, and comparing 
them with those which served as the basis of my first edition, 
in order to deduce thence new approximations or new subdi- 
visions, and then by searching in all the books I could pro- 
cure for the genera or subgenera established by naturalists, 
and the description of species by which they have supported 
these different combinations. 
The study of synonymes has become much easier now than 
it was at the period of my first edition. Both French and 
(1) See my Discourse before the Institute on the “ Progrés de l’Histoire Natu- 
relle depuis la paix maritime,” published in the third volume of my “ Eloges.” 
