130 NINETEENTH CENTURY. FT. HI. 



shut up lose the power of using their wings, as has been the 

 case with our domestic poultry. Man can make a number 

 of different varieties both of plants and animals by merely 

 keeping those which have the peculiarities he admires. The 

 different kinds of pigeon, for example the pouters, fan-tails, 

 tumblers, and others, which are so unlike each other are 

 said by naturalists to be all descendants of the common 

 rock-pigeon ; and all the varieties, of rabbit have come from 

 one wild species. You cannot find a wild pigeon with a 

 fan-tail, or a wild rabbit with lop-ears. 



If man, then, in a few hundred years can make such 

 changes, ' is it not possible,' said Lamarck, ' that nature in 

 all the long ages during which the world has existed may 

 have produced the different kinds of plants and animals by 

 gradually enlarging one part and diminishing another to suit 

 the wants of each ? ' These and many other arguments 

 Lamarck brought forward in his work in 1801, and again in 

 his 'Philosophic Zoologigue' in 1809, to prove that the way 

 in which the Creator has formed different plants and animals 

 has been by altering them gradually out of simple forms. 



There was, however, one very weak point in all his argu- 

 ments ; he did not show sufficiently what should cause living 

 beings to go on altering, and becoming more and more dif- 

 ferent. For if you turn plants and animals, which man has 

 altered, out into the fields again, in a very few generations 

 they return very nearly to their old forms ; nor can we see 

 any reason why the differences between animals should go 

 on increasing unless they were picked out and kept apart, 

 as men keep them when they want to get new varieties. 



Lamarck did, indeed, point out that climate and dif- 

 ference of food would help to alter the nature of an animal, 

 but the chief reason he gave for changes taking place in 

 them was that the animal itself might cause the alteration in 



