EVOLUTION xxxi 



during the last few thousand years : hence no change need 

 have been expected in the animals living there. 



Lamarck then considers the question whether it is true 

 that any species have ever become extinct. The evidence 

 of fossils certainly seems to suggest it, for they exhibit 

 innumerable forms no longer found among living animals. 

 Yet Lamarck finds it very difficult to believe that nature 

 could be so imperfect as to permit of the complete extinction 

 of any species. He was not wholly emancipated from that 

 vicious tendency — of which Plato was the prototype — towards 

 imagining, that because a thing was not beautiful, or har- 

 monious, or otherwise agreeable, it could not be true. Hence 

 he inferred that, in the case of many fossils of apparently 

 extinct species, the species would still be found living in 

 unexplored countries, or on the sea-bottom, or other unknown 

 regions. He believed furthermore that many of these fossils 

 had evolved into existing known species ; but that the 

 changes undergone during evolution, in correspondence with 

 a changing environment, had been so great that the existing 

 species were no longer recognisable as descendants of the 

 fossils. 



If any species have become extinct it is, he said, at all 

 events only the larger species of land animals, such as 

 Cuvier's Palaeotherium, Anoplotherium, Mastodon, etc. : and 

 their extermination, if a fact, is exclusively due to human 

 agency. But no species of water animals, nor any of the 

 smaller species of land animals, can possibly have become 

 extinct. Lamarck very shrewdly perceived that the fossils 

 showing most analogy with living forms are usually the 

 least ancient. And this strange admixture of good and 

 bad philosophy then ends in an attack upon the theory of 

 a general catastrophe in nature — a theory invoked to explain 

 among other things the divergence of fossils from existing 

 forms of life. Throughout this part of Lamarck's work, we 

 find much in which his philosophy was several generations 

 in advance of his contemporaries, and indeed was not far 

 short of our own : mixed with much else in which his 



