Alfred Russel Wallace 



in ''The World of Life" (1910), of an over-ruling God, of 

 the spiritual nature of man, and of the other world of 

 spiritual beings. 



An essay that excited special attention was that on 

 Mimicry. The two on Birds' Nests brought forth some 

 rather heated correspondence from amateur naturalists, to 

 which Wallace replied either by adducing confirmation of 

 the facts stated, or by thanking them for the information 

 they had given him. 



With reference to the paper on Mimicry, it is in- 

 teresting to note that the hypothesis therein adopted was 

 first suggested by H. W. Bates, Wallace's friend and 

 fellow-traveller in South America. The essay under this 

 title dealt with the subject in a most fascinating manner, 

 and was probably the first to arouse widespread interest 

 in this aspect of natural science. 



The next eight years saw the production of many im- 

 portant and valuable works, amongst which the " Geo- 

 graphical Distribution of Animals " (1876) occupies the 

 chief place. This work, though perhaps the least known 

 to the average reader, was considered by Wallace to be 

 the most important scientific work he ever attempted. 

 From references in letters written during his stay in the 

 Malay Archipelago, it is clear that the subject had a 

 strong attraction for him, and formed a special branch of 

 study and observation many years before he began to work 

 it out systematically in writing. His decision to write the 

 book was the outcome of a suggestion made to him by 

 Prof. A. Newton and Dr. Sclater about 1872. In addition 

 to having already expressed his general views on this sub- 

 ject in various papers and articles, lie had, 43fter careful 

 consideration, come to adopt Dr. Sclater's division of the 

 earth's surface into six great zoological regions, which he 

 found equally applicable to birds, mammalia, reptiles, and 



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