Reactions to On the Origin of Species stage where he was able to turn his attention fully to "Species", and from this point he was working to publish his theory. On 18 June 1858 he received a parcel from Alfred Russel Wallace enclosing about twenty pages describing an evolutionary mechanism that was similar to Darwin's own theory. Darwin put matters in the hands of his friends Lyell and Hooker, who agreed on a joint presentation to the Linnean Society on 1 July 1858. Their papers were entitled, collectively, "On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means
Genetics and the Origin of Species of Species" in 1859." Dobzhansky was plagued by a form of leukemia in his later years, but he remained vigorously active until the day before his death on December 18, 1975. During his lifetime he was the recipient of many honors and awards. For "Genetics and the Origin of Species" Dobzhansky was awarded the Daniel Giraud Elliot Medal from the National Academy of Sciences in 1941. Sixty years after its publication, the National Academy of Sciences commissioned a book entitled "Genetics and the Origin of Species: From Darwin to Molecular Biology 60 Years After Dobzhansky". It was also included in