428 BIOGRAPHICAL SKETCHES. 



1844, being a part of the manuscript of a chapter in his 

 44 Origin of Species ; " also of a private letter addressed to 

 the writer of this memorial in October, 1857, — the publica- 

 tion of which (in the Journal of the Proceedings of the Lin- 

 ngean Society, Zoological Part, iii. 45-53, issued in the sum- 

 mer of 1858) was caused by the reception by Darwin himself 

 of a letter from Mr. Wallace, inclosing a brief and strikingly 

 similar essay on the same subject, entitled " On the Tendency 

 of Varieties to depart indefinitely from the Original Type." 

 Mr. Darwin's action upon the reception of this rival essay 

 was characteristic. His own work was not yet ready, and the 

 fact that it had been for years in preparation was known only 

 to the persons above mentioned. He proposed to have the 

 paper of Mr. Wallace (who was then in the Moluccas) pub- 

 lished at once, in anticipation of his own leisurely prepared 

 volume ; and it was only under the solicitation of his friends 

 cognizant of the case that his own early sketch and the cor- 

 roboratory letter were printed along with it. 



The precursory essays of Darwin and Wallace, published 

 in the Proceedings of a scientific society, can hardly have been 

 read except by a narrow circle of naturalists. Most thought- 

 ful investigating naturalists were then in a measure prepared 

 for them. But toward the close of the following year (in the 

 autumn of 1859) appeared the volume " On the Origin of 

 Species by means of Natural Selection, or the Preservation of 

 Favored Races in the Struggle for Life," the first and most 

 notable of that series of duodecimos which have been read 

 and discussed in almost every cultured language, and which 

 within the lifetime of their author have changed the face and 

 in some respect the character of natural history, — indeed 

 have almost as deeply affected many other lines of investiga- 

 tion and thought. 



In this Academy, where the rise and progress of Darwinian 

 evolution have been attentively marked and its bearings criti- 

 cally discussed, and at this date, when the derivative origin of 

 animal and vegetable species is the accepted belief of all of us 

 who study them, it would be superfluous to give any explana- 

 tory account of these now familiar writings ; nor, indeed, 



