LAMARCK’S THEORY OF EVOLUTION 269 
viduals; and in that way the progress acquired in the 
composition of the organization and in the forms and 
the diversity of the parts has been preserved. 
“os. That with the aid of sufficient time, of circum- 
stances which have been necessarily favorable, of 
changes that all parts of the surface of the globe have 
successively undergone in their condition—in a word, 
with the power that new situations and new habits 
have in modifying the organs of bodies endowed with 
life—all those which now exist have been impercep- 
tibly formed such as we see them. 
“6, Finally, that according to a similar order of 
things, living beings, having undergone each of the 
more or less great changes in the condition of their 
organization and of their parts, that which is desig- 
nated as a species among them has been insensibly 
and successively so formed, can have only a relative 
constancy in its condition, and cannot be as ancient 
as nature. 
“ But, it will be said, when it is necessary to suppose 
that, with the aid of much time and of an infinite vari- 
ation in circumstances, nature has gradually formed 
the different animals that we know, would we not be 
stopped in this supposition by the sole consideration 
of the admirable diversity which we observe in the 
instinct of different animals, and by that of the 
marvels of all sorts which their different kinds of 
industry present ? 
“Will one dare to carry the spirit of system (forter 
Lesprit de systtme)to the point of saying that it is 
nature, and she alone, which creates this astonishing 
diversity of means, of ruses, of skill, of precautions, 
of patience, of which the industry of animals offers us 
so many examples! What we observe in this respect 
in the class of insects alone, is it not a thousand times 
more than is necessary to compel us to perceive that 
the limits of the power of nature by no means permit 
her herself to produce so many marvels, and to force 
