a 
Bit THE ORIGIN OF SPECIES 67 
7 the purpose in view. It is a physiological fact, 
he says, that organs are increased in size by 
_ action, atrophied by inaction; it is another 
_ physiological fact that modifications produced _are 
_ transmissible to offspring. Change the actions of 
an animal, therefore, and you will change its 
_ structure, by increasing the development éf the 
‘parts newly brought inks use and by the diminu- 
tion of those less used; but by altering the 
circumstances which surround it you will alter its 
actions, and hence, in the long run, change of 
circumstance must produce change of organisation. 
All the species of animals, therefore, are, in 
Lamarck’s view, the result of the indirect action 
_ of changes of circumstanc., upon those primitive 
_ germs which he considered to have originally 
arisen, by spontaneous generation, | within the 
waters of the globe. It 1s curious, however, that 
Lamarck should insist so strongly ! as he has done, 
that circumstances never in any degree directly 
_ modify the form or the organisation of animals, 
but only operate by changing their wants and 
consequently their actions; for he thereby brings 
upon himself the obvious question, How, then, do 
plants, which cannot be said to have wants or 
actions, become modified? To this he replies, 
that they are modified by the changes in their 
nutritive processes, which are effected by changing 
circumstances; and it does not seem to have 
1 See Phil. Zoologique, vol. i. p. 222, et seq. 
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