1 PROLEGOMENA. 5 



cess in the vegetation of the downs is seen in the 

 turf, with its weeds and gorse. Under the con- 

 ditions, they have come out of the struggle vic- 

 torious; and, by surviving, have proved that they 

 are the fittest to survive. 



That the state of nature, at any time, is a 

 temporary phase of a process of incessant change, 

 which has been going on for innumerable ages, 

 appears to me to be a proposition as well estab- 

 lished as any in modern history. Paleontology 

 assures us, in addition, that the ancient phi- 

 losophers who, with less reason, held the same 

 doctrine, erred in supposing that the phases 

 formed a cycle, exactly repeating the past, exactly 

 foreshadowing the future, in their rotations. On 

 the contrary, it furnishes us with conclusive 

 reasons for thinking that, if every link in the 

 ancestry of these humble indigenous plants had 

 been preserved and were accessible to us, the whole 

 would present a converging series of forms of 

 gradually diminishing complexity, until, at some 

 period in the history of the earth, far more remote 

 than any of which organic remains have yet been 

 discovered, they would merge in those low groups 

 among which the boundaries between animal and 

 vegetable life become effaced.* 



p. 304. In the address on "Geological Contemporaneity 

 and Persistent Types" (1862), the paleontological proofs 

 of this proposition were, I believe, first set forth. 



* " On the Border Territory between the Animal and 

 the Vegetable Kingdoms," Essays, vol. viii. p. 162. 



