Darwin-Wallace Celebration. 85 



by the late Robert Brown, Esq., both to the Linnean 

 Society and to Botanical Science, by the entire devotion 

 of a long life and of talents of the highest order to the 

 promotion of the great objects for which the Society 

 was formed. 



" That it looks back with heartfelt satisfaction to the 

 long period of sixty years, during which Mr. Brown was 

 connected with the Society, as an Associate, as Librarian, 

 as a Fellow, as a Vice-President, and as President, and 

 is profoundly sensible of the 'honour which the Society 

 has derived from this long and intimate connexion with 

 so great a Master in Botanical Science. 



" That while thus recording its high appreciation of 

 the eminent talents of this great man, and of their suc- 

 cessful application to the pursuit of Natural Science, 

 this Meeting cannot refrain from also paying a just 

 tribute to the simple-hearted benevolence of disposition, 

 the high moral purity of mind, and the unswerving 

 rectitude of judgment, which formed the most striking 

 distinctions of his individual character. 



" That influenced by these various considerations, 

 this Meeting deeply deplores the loss which the Linnean 

 Society and Natural Science have sustained by the 

 death of so distinguished, and at the same time, so 

 estimable, a man/' 



Read 1st, a letter from Sir Charles Lyell, F.L.S., and 

 Dr. Hooker, F.L.S., addressed to the Secretary, as intro- 

 ductory to the following Papers, on the laws which affect the 

 production of varieties, races, and species, viz. : 



An abstract from a MS. work on species, by Charles 

 Darwin, Esq., F.R.S. & L.S., sketched in 1839 and 

 copied in 1844. 



An abstract of a letter addressed by Mr. Darwin to 

 Prof. Asa Gray of Boston, U.S., in Oct. 1857. 



An essay on the tendency of varieties to depart inde- 

 finitely from the original type ; by A. R. Wallace, Esq. 



