PRE rAaee, 
N the autumn of 1847 Mr. A. R. Wallace, who has since 
l acquired wide fame in connection with the Darwinian theory 
of Natural Selection, proposed to me a joint expedition to the 
river Amazons, for the purpose of exploring the Natural History 
of its banks; the plan being to make for ourselves a collection 
of objects, dispose of the duplicates in London to pay expenses, 
and gather facts, as Mr. Wallace expressed it in one of his 
letters, “towards solving the problem of the origin of species,” 
a subject on which we had conversed and corresponded much 
together. We met in London early in the following year to 
study South American animals and plants at the principal 
coliections ; and in the month of April, as related in the 
following narrative, commenced our journey. 
My companion left the country at the end of four years; 
and, on arriving in England, published a narrative of his 
voyage, under the title of “ Travels on the Amazons and Rio 
Negro.” I remained seven years longer, returning home in 
July 1859; and having taken, after the first two years, a 
different route from that of my friend, an account of my 
separate travels and experiences seems not an inappropriate 
offering to the public. 
When I first arrived in England, being much depressed in 
health and spirits after eleven years’ residence within four 
