WALLACE'S ESSAY. 77 



" may, it is believed, be followed out so as to agree 

 with all the phenomena presented by organised 

 beings, their extinction and succession in past ages, 

 and all the extraordinary modifications of form, 

 instinct, and habits which they exhibit." 



Wallace's Essay has been reprinted without 

 alteration in his " Essays on Natural Selection," 

 recently re-issued combined with " Tropical Nature." 



