50 SPECIES NOT 



veloped into an oyster, the ojster into a crab, 

 the crab into a fish, the fish into a reptile, the 

 reptile into a bird, and the bird into a mammal? 

 I look upon his views in a different light. I 

 regard his theory to mean that starting from any 

 one point his forms, are an infinity of divergences 

 ultimately terminated in species as we see them ; 

 the lives being long or short according to the po- 

 sition of the organisms in the scale, and that he 

 does not inculcate the necessity of passing through 

 the phases you have just quoted." 



To the naturalist of course I need not reply 

 to this observation. If Mr. Darwin's theory 

 means anything, it means progressive development. 

 He expressly states that each stare of variation 

 must be for the benefit of the individual, which 

 benefit in the "struggle for existence" he turns 

 to his own account. But if Mr. Darwin does 

 not mean that his species have passed through 

 the phases of existence as exemplified by modern 

 classifiers, his theory becomes infinitely more im- 

 probable, because the difference between interme- 

 diate forms must have been much greater, and 

 the chances of their being formed by "natural 

 selection" still greater also. Thus, what corres- 

 ponds to the heart of higher animals, in the 

 insect is a mere dilated tube; this in the fish 

 is differentiated into a heart with an auricle 

 and ventricle; in the reptile there are three 

 Cavities, in the bird and mammal four. Now as 

 each of these hearts are peculiarly adapted to 

 the condition of life of the individual species, Mr. 



