iv MODERN E VOL UTION 127 



and Wallace, who was accompanied by his younger 

 brother, parted company, * rinding it more convenient 

 to explore separate districts and collect independ- 

 ently.' Wallace took the northern parts and tribu- 

 taries of the Amazons, and Bates kept to the main 

 stream, which, from the direction it seems to take 

 at the fork of the Rio Negro, is called the Upper 

 Amazons or the Solimoens. Different in character 

 and climatic conditions from the Lower Amazons, it 

 flows through a ' vast plain about a thousand miles 

 in length, and five hundred or six hundred miles in 

 breadth, covered with one uniform, lofty, impervious- 

 and humid forest/ Bates stayed in the country till 

 June 1859, but Wallace left in 1852, and in the 

 following year published an account of his journey 

 under the title of Travels on the Amazon and Rio 

 Negro. That book was written under the serious 

 disadvantage of the destruction of the greater part 

 of the notes and specimens by the burning of the 

 ship in which Mr. Wallace took passage on his 

 homeward voyage. That it remains one of the 

 select company of works of travel for which demand 

 is continuous is evidenced in a reprint which appeared 

 in 1891. If it affords few hints of the author's bent 

 of mind towards the question of the origin of species, 

 it shows what interest was being aroused within him 

 over the allied subject of the geographical distribu- 

 tion of plants and animals which Mr. Wallace was 

 to make so markedly his own. 



In 1854 he sailed for the Malay Archipelago, 

 where nearly eight years were spent in exploring the 

 region from Sumatra to New Guinea. The large 

 and varied outcome of that labour was embodied in 



