72 



Cincinnati Society of Natural History. 



man}- editions it has gone through, and by its having been adopted as 

 a book for children, by putting the narrative into simple language. 



In 1846 was published his "Geological Observations upon South 

 America,'' a volume of 268 pages, which was one of the results of his 

 voyage in the Beagle. His monograph of the sessile and pedunculate 

 Cirripedia, with figures of all the species, was published in two parts 

 in 1851 and 1854, and is replete with interesting and valuable notes 

 upon their life history. Another monograph, on the Fossil Lepadidse 

 of Great Britain, was published by the Palaeontological Society of Eng- 

 land in 1851, and these works show Mr. Darwin to have been as great 

 an authority in special branches as he has since been recognized to be 

 in the wide field of Biology. 



It was while upon his voyage round the world, that Mr. Darwin first 

 had suggested to him the ideas afterward embodied in his " Origin of 

 Species," and from the time of his return from his first and only long 

 journey, in 1836, until his death, he was engaged in work which tended 

 to confirm and establish his first ideas. It was the reading of the cele- 

 brated treatise of Malthus on "The Principles of Population," which 

 originally directed his ideas toward the matter of the "Struggle for 

 Existence," which forms so prominent a part of his great theory. 

 When the "Vestiges of Creation'' first appeared, in 1844, an epoch be- 

 gan which will be long remembered in the history of science. Although 

 about 1830 the great Cuvier had ridiculed and vanquished his oppo- 

 nent Geoffroy St. Hiliare, before the Paris Academy of Sciences, the 

 theories of Lamarck and of St. Hiliare had their influence upon think- 

 ing men. Though many of the ideas were crude and improbable, they 

 contained germs of truths which were afterward fully elaborated. 



For twent}^ years previous to the publication of Mr. Darwin's "Origin 

 of Species," the work b}' which he is most widel} T known, he was en- 

 gaged in collecting facts and making observations into the natural 

 history of the animal kingdom. His friends. Sir Charles Lj^elJ, and 

 Sir Joseph Hooker, names which will descend to posterity with no 

 small amount of fame attached to them, were cognizant of his labors in 

 this field, and repeated^ urged him to make an abstract of his ob- 

 servations for the benefit of science. This he had as often refused to 

 do, not being satisfied with the materials at his command. But in 

 1858, Mr. Alfred Wallace, then traveling in the Malay archipelago, 

 sent home an article "On the Tendency of Varieties to depart indefin- 

 itely from the Original T3 r pe," with the request that if thought worthy 

 it be read before the Linnean Societ}'. Then Mr. Darwin was induced 



