8o CHARLES DARWIN 



equatorial zone strange puzzles to engage their deepest 

 attention ; they recognised in the veins and spots that 

 diversified the filmy membranes of insects' wings the 

 hieroglyphs of nature, writing as on a tablet for them 

 to decipher the story of the slow modification of species. 

 In 1852 the year when Herbert Spencer in England 

 published his essay on the ' Development Hypothesis,' 

 and when Naudin in France put forth his bold and able 

 paper on the * Origin of Species ' Wallace once more 

 returned to Europe, and gave to the world his interest- 

 ing ' Travels on the Amazons and the Rio Negro.' Two 

 years later the indefatigable traveller set out a second 

 time on a voyage of tropical exploration, among the 

 islands of the Malay archipelago, and for eight years 

 he wandered about in Malay huts and remote islets, 

 gathering in solitude and isolation the enormous store 

 of minute facts which he afterwards lavished with so 

 prodigal a hand upon ' Tropical Nature,' and the ' Geo- 

 graphical Distribution of Animals.' 



While Wallace was still at Amboyna, he sent home 

 in 1858 a striking memoir, addressed to Darwin, with a 

 request that he would forward it to Sir Charles Lyell, for 

 presentation to the Linnean Society. Darwin opened 

 and read his brother naturalist's paper, and found to his 

 surprise that it contained his own theory of natural 

 selection, not worked out in detail, as he himself was 

 working it out, but still complete in spirit and essence, 

 with no important portion of the central idea lacking to 

 its full rotundity of conception. A jealous man would 

 have thrown obstacles in the way of publication ; but 

 both Darwin and Wallace were born superior to the 

 meannesses of jealousy. The elder naturalist commended 



