SPONTANEOUS GENERATION. 129 



place until some variation had occurred, making possible 

 the occupation of new regions, or of the old regions, 

 under new conditions. But the new species, constituted 

 by some advantageous variation, would be likely to 

 overrun the whole field, to the almost complete sup- 

 pression of the earlier and more simple form. The dis- 

 tance thus gained in the race of progressive organization 

 it would be likely not only to maintain, but greatly to 

 increase. Its descendants would vary in more than one 

 useful direction, till it might, as we have said, become 

 the parent of all the conspicuous members of the earth's 

 population. The earliest and simplest form might still 

 have representatives inheriting its likeness by direct 

 descent, but unable to make their way in the world, not 

 from wanting the power to vary, but from finding the 

 world pre-occupied by species too powerful for them to 

 compete with. In this way they would be restrained to 

 their original insignificance. 



Now exactly the same result would follow, if, instead 

 of being born in what we consider the ordinary course 

 of parentage, these simple forms were ever being spon- 

 taneously generated. They would find the world pre- 

 occupied against their advancement in the scale of 

 organization; they would rarely, if ever, be allowed 

 to lead up by successive useful variations to highly- 

 organized forms; and if ever, only in periods of time 

 so enormous as to perplex the acutest human under- 

 standing. 



What is commonly supposed to be the Biblical theory of 

 Creation, is in truth a theory of spontaneous generation, 



K 



