222 THE DOCTRINE OF DESCENT. 



The Geographical Distribution of Animals in the light of the Doctrine of 



Derivation. 



Although ever since the century of the great geo- 

 graphical discoveries, material has been accumulating 

 for a geography of plants and animals, the foundations 

 of scientific botanical geography (apart from George 

 Forster's observations) were first contained in Hum- 

 boldt's celebrated ''Ideas on the Physiognomy of Plants" 

 (Ideen zu einer Physiognomik der Gewachse). It is the 

 first description of vegetal forms, comprising the entire 

 area of the earth, and the manner in which, singly or 

 combined, they lend a characteristic impress to the 

 landscape of their region of distribution, and again on 

 their side harmonize with the other factors of the scene. 

 The celebrated founder of Climatology, who circled tiie 

 terrestrial globe with lines of equal temperature, of 

 equal inclination and declination of the magnetic needle, 

 and divided it into dry and rainy zones, knew better 

 than any of his contemporaries that the animal and 

 vegetal world depended on all these factors. Yet 

 neither he nor his followers, before Darwin, rose higher 

 than the description of Nature, which had already 

 checked Bufifon in his grand picture of Nature, '' Les 

 Epoques de la Nature." 

 A natural result of the extraordinary extension of 



