xil PREFACE TO THE FIRST EDITION. 
M. de Lamarck, in which will be found all that the most ar- 
dent thirst for knowledge can desire. 
As regards Insects, which, by their external form, organi- 
zation, habits, and influence on all animated nature, are so 
highly interesting, I have been fortunate enough to find assis- 
tance, which, in rendering my work infinitely more perfect 
than it could have possibly been had it emanated from my pen 
alone, has at the same time considerably accelerated its publica- 
tion. My friend and colleague M. Latreille, who has studied 
these animals more profoundly than any other man in Europe, 
has kindly consented to give, in a single volume, and nearly 
in the order adopted for the other parts, a summary of his 
immense researches, and an abridged description of those in- 
numerable genera entomologists are continually establishing. 
As for the rest, if in some places I have given less extent 
to the exposition of subgenera and species, all that relates to 
the superior divisions and the indicia of relations, I have 
founded on bases equally solid, by assiduous and universal re- 
searches. 
I have examined, one by one, all the species of which I 
could procure specimens; I have approximated those which 
merely differed from each other in size, colour, or in the 
number of some parts of little importance, and have formed 
them into what I denominate subgenera. 
Every time it was possible, I dissected one species at least 
of each subgenus, and if those be excepted to which the 
scalpel cannot be applied, but very few groups of this degree 
can be found in my work, of which I cannot produce some 
considerable portion of the organs. 
Having determined the names of the species I observed, 
which had been previously either well described or well 
figured, I placed in the same subgenera those I had not 
seen, but whose exact figures, or descriptions, sufliciently 
precise to leave no doubt remaining as to their natural rela- 
tions, I found in authors; but I have passed over in silence 
that great number of vague indications, on which, in my opi- 
nion, naturalists have been too eager to establish species, 
