EPOCHS IN BIOLOGICAL HISTORY 411 



further discovery of principles." The Origin of Species 

 brought biology into line with the other inductive sciences, 

 recast practically all of its problems, and instituted new ones. 

 Darwin beautifully and conservatively expressed this new 

 outlook on nature in the historically important concluding 

 paragraph of his epoch-making work: 



"It is interesting to contemplate a tangled bank, clothed 

 with many plants of many kinds, with birds singing on the 

 bushes, with various insects flitting about, and with worms 

 crawling through the damp earth, and to reflect that these 

 elaborately constructed forms, so different from each other, 

 and dependent upon each other in so complex a manner, have 

 all been produced by laws acting around us. These laws, 

 taken in the largest sense, being Growth with Reproduction; 

 Inheritance which is almost implied by reproduction; Varia- 

 bility from the indirect and direct action of the conditions of 

 life, and from use and disuse : a Ratio of Increase so high as to 

 lead to a Struggle for Life, and as a consequence to Natural 

 Selection, entailing Divergence of Character and the Extinc- 

 tion of less-improved forms. Thus, from the war of nature, 

 from famine and death, the most exalted object which we are 

 capable of conceiving, namely, the production of the higher 

 animals, directly follows. There is a grandeur in this view 

 of life, with its several powers, having been originally breathed 

 by the Creator into a few forms or into one; and that, whilst 

 this planet has gone cycling on according to the fixed law 

 of gravity, from so simple a beginning endless forms most 

 beautiful and most wonderful have been, and are being 

 evolved." 



