THE LIFE AND WORK OF DARWIN 20 



Fuego and the Falkland Islands, and rather mon 

 than a year on the western coast. Darwin wen 

 partly with the ship, but s pent loj ig_jieriods„_oi 

 shore, travelling over much country, collecting 

 observing, andjhiinking. 



Darwin's most important overland journey was ii 

 1833 from Rio Negro to Bahia Blanca, and theno 

 five hundred miles further on to Buenos Ayres 

 During this journey over Pampas he discovered th 

 remains of vast numbers of extinct animals, some c 

 enormous dimensions, such as the Megatherium ani 

 the Mylodon, which were found in gravel fifteen to 

 twenty feet above the sea level near Bahia BlancE 

 It was here that Darwin was much struck with th 

 relations between living and extinct forms. " Thi 

 wonderful relationship," he writes, "in the sam 

 continent between the dead and the living, will, I d 

 not doubt, hereafter throw more light on the appeal 

 ance of organic beings on our earth, and their dis 

 appearance from it, than any other class of facts. 

 He noticed the replacement of huge extinct form 

 by unlike yet allied forms, and that species ar 

 replaced, but by allied species. Darwin was im 

 pressed rather with their resemblances than thei 

 differences, whereas Cuvier, we saw, was most struc 

 with the differences. He was also much impressei 

 with the evidence of changes in the land in recen 

 times, a point which laid the foundation of his theor 

 of coral reefs. At Tierra del Fuego he was struc 

 with the characters of savage races, and noted th 

 almost entire absence of everything which we regar* 

 as characteristically human. 



