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devoured ; those whose flowers are most conspicuous may be soonest 

 fertilized by insects. We cannot doubt that, on the whole, any benefi- 

 cial variation will give the possessors of it a greater probability of 

 living through the tremendous ordeal they have to undergo. There may 

 be something left to what may be called chance, but on the whole " the 

 fittest will survive." Then we have another important fact to consider, — 

 the principle of heredity or transmission of variations. If we grow 

 plants from seed or breed any kind of animals, year after year, consu- 

 ming or giving away all the increase we do not wish to keep just as they 

 come to our hand, our plants and animals will continue much the same ; 

 but if we every year carefully save the best seed to sow, and the finest 

 or brightest colored animals to breed from, we shall soon find that an 

 improvement will take place, and that the average quality of our stock 

 will be raised. This is the way in which all our fine garden fruits and 

 vegetables and flowers have been produced, as well as our splendid breeds 

 of domestic animals ; and they have thus become, in many cases, so 

 different from the wild races from which they originally sprung as to 

 be hai'dly recognizable as the same. It is, therefore, proved that if any 

 particular kind of variation is preserved and bred from, the variation 

 itself goes on increasing in amount to an enormous extent, and the 

 bearing of this on the origin of species is most important ; for if in each 

 generation of a given animal or plant the fittest survive to continue the 

 breed, then whatever may be the peculiarity that causes fitness in the 

 particular case that peculiarity will go on increasing and strengthening 

 so long as it is usejul to the species. But as soon as it has reached its 

 maximum of usefulness, and some other qualification or modification 

 would help in the struggle, then the individuals which vary in the new 

 direction will survive ; and thus a species may be gradually modified? 

 first in one direction and then in another, till it differs from the original 

 parent form as much as the greyhound differs from any wild dog or the 

 cauliflower from any wild plant. But animals or plants which thus 

 differ in a state of nature are always classed as distinct species, and 

 thus we see how by the continuous survival of the fittest, or the pre- 

 servation of favored laces in the struggle for life, new species may be 

 originated. Past time has been to all intents and purposes infinite. 

 Hence it is probable that the existent species of animals and plants have 



