Great Men and their Environment - a lecture by Henry James. "A remarkable parallel, which I think has never been noticed, obtains between the facts of social evolution on the one hand, and of zoölogical evolution as expounded by Mr. Darwin on the other."
An early precursor of memetic thought.
Memetics - at Principia Cybernetica. Cultural evolution can be modelled through principles of variation and selection very similar to Darwinism.