184 EVOLUTION AND DOGMA. 



dogs shown at our expositions, will certainly give 

 the same answer as I do. 



" Infertility among species, therefore, has, in the 

 organic world, a role which is almost analogous to 

 gravitation in the sidereal world. It preserves the 

 zoological or botanical distance among species, as 

 attraction maintains the physical distances among 

 the stars. Both have their perturbations, their un- 

 explained phenomena. But, has anyone called in 

 question the great fact which fixes in their respective 

 places both satellites and suns ? No. And can one, 

 on this account, deny the fact which assures the sep- 

 aration of species the most closely allied, as well as 

 of groups the most widely separated? By no means. 

 In astronomy we should reject incontinently every 

 hypothesis in opposition to the first. And, although 

 the complication of phenomena is much greater in 

 botany and zoology, serious study will always lead 

 us to discard all doctrines that are at variance with 

 the second." ' 



Infertility among distinct species, as De Quatre- 

 fages here views the matter, is thus seen to be de- 

 manded by the fitness of things. It is required for 

 the harmony of animated nature, and is rendered 

 necessary by the hopeless confusion which would re- 

 sult if such infertility did not exist. 



But the argument from infertility, as urged 

 against evolutionists, has even greater force when 

 regarded from another point of view I mean from 

 the standpoint of fact. Evolution, it is alleged, is 

 disproved, not because it seems fit and necessary 



lu Darwin et ses Precurseurs Franjais," pp. 259 and 260. 



