The idea that Darwin rejected Lamarck’s ideas of use and disuse and the inheritance of acquired traits emerged in the late nineteenth century as biologists debated the mechanisms by which evolution occurs.  In characterizing “pure Darwinism,” critics and enthusiasts alike sought to purge Darwinism of any reliance on the idea that changes acquired in the as the result of the use or disuse of organs could be passed along to the next generation via heredity.  But Darwin himself was a strong believer in the idea.  Through the successive editions of the Origin of Species he represented the inheritance of acquired characters as an important supplement to natural selection. In his Variation of Animals and Plants under Domestication, he not only gave examples of the inherited effects of use and disuse, but he was also pleased to propose how his “Provisional Hypothesis of Pangenesis” could successfully explain the phenomenon.  August Weismann’s attacks on the inheritance of acquired characters, beginning in the 1880s, were the primary impetus for the idea’s decline in popularity among biological theorists – and ultimately for the widespread forgetting of the fact that this was an idea that Darwin himself explicitly endorsed.