72 EVOLUTION AND DOGMA. 



they discourse on " the circumstances of the en- 

 vironment," the conditions of life, or the monde 

 ambiant, of Geoffrey Saint-Hilaire. Leibnitz in his 

 " Protogaea " expresses similar views on the continuity 

 of species, that is, of a graduated series of living 

 forms " that in each remove differ very little from 

 one another." Distinct evolutionary views had like- 

 wise been propounded by Spinoza, Herder and 

 Schelling, but it is unnecessary to dwell on them here. 

 In its growth, then, the modern theory of Evolu- 

 tion may aptly be compared with that of the cen- 

 tury plant. For long generations it had been gath- 

 ering material and strength, but at last, suddenly 

 and almost unexpectedly, it blossomed forth into a 

 working hypothesis of colossal proportions and uni- 

 versal application. Philosophy anticipated many, if 

 not all its leading tenets, but it was inductive science 

 which placed it on the foundation on which it now 

 rests and which gave it the popularity that it now 

 enjoys. 



Species and Creation. 



The pervading idea of Evolution, as we have 

 seen, is one of change, the idea of integration and 

 differentiation. As applied to plants and animals it 

 is the development, by the action of natural causes, 

 of the higher from the lower forms. 



The various forms of animal and plant life ac- 

 cording to this view are genetically related to one 

 another. Species are therefore not immutable as 

 is generally imagined, but mutable. What we call 

 species are the results of descent with modification, 



