272 THE HISTORY OP CREATION. 



of animals and plants are variable, and possess the capability 

 of adapting themselves to different places or to local rela- 

 tions. The varieties or races of each species, according to 

 the laws of adaptation, deviate all the more from the original 

 primary species, the greater the difference of the new con- 

 ditions to which they adapt themselves. If we imagine 

 these varieties — which have proceeded from a common 

 primary form — to be disposed in the shape of a branching, 

 radiating bunch, then those varieties will be best able to 

 exist side by side and propagate which are most distant 

 from one another, which stand at the ends of the series, or 

 at the opposite sides of the bunch. Those forms, on the 

 other hand, occupying a middle position — presenting a state 

 of transition — have the most difficult position in the struggle 

 for life. The necessaries of life differ most in the two ex- 

 tremes, in the varieties most distant from one another, and 

 consequently these will get into the least serious conflict 

 with one another in the general struggle for life. But the 

 intermediate forms, which have deviated less from the 

 original primary form, require nearly the same neces- 

 saries of life as the original form, and therefore, in com- 

 peting for them, they will have to struggle most with, and be 

 most seriously threatened by, its members. Consequently, 

 when numerous varieties of a species live side by side on the 

 same spot of the earth, the extremes, or those forms deviating 

 most from one another, can much more easily continue to 

 exist beside one another than the intermediate forms which 

 have to struggle with each of the different extremes. The 

 intermediate forms will not be able to resist, for any length 

 of time, the hostile influences which the extreme forms 

 victoriously overcome. These alone maintain and propagate 



■V. 



