162 EVOLUTION AND DOGMA. 



competent to deal with them, and flourish in them, 

 than the derived forms, then in the struggle for exis- 

 tence the parent form will maintain itself and the 

 derived forms will be exterminated. But if, on the 

 contrary, the conditions are such as to be more fa- 

 vorable to a derived than to a parent form, the parent 

 form will be extirpated and the derived form will take 

 its place. In the first place there will be no pro- 

 gression, no change of structure, through any 

 imaginable series of ages ; and in the second place 

 there will be modification and change of form." ' 



Paucity of Transitional Forms. 



The second objection, like the preceding, is an 

 obvious one, and at first sight equally plausible. It 

 is based on the paucity of transitional forms, or 

 " missing links," in the various sedimentary strata of 

 the earth's crust. At first blush the objection 

 seems to be fatal to the theory of Evolution, as it 

 certainly would be fatal, if well founded, to the the- 

 ory of natural selection, which supposes that species 

 have advanced from lower to higher forms by infini- 

 tesimal increments. So much importance, indeed, 

 does Darwin attach to this objection, that he devotes 

 a whole chapter in his " Origin of Species " to its so- 

 lution. And although he frankly admits that the 

 geological record, so far as at present known, still 

 opposes insuperable difficulties to his theory of nat- 

 ural selection, it does not follow, as we shall see far- 

 ther on, that such difficulties can validly be urged 



1 " Science and Hebrew Tradition," pp. 83 and 84. 



