I think the more likely possibility is that the neo-evolutionists whose main desire is to perpetuate the myth of macroevolution have purposely posted links to the wrong letter. I could be wrong, but I doubt it.
That really doesn't matter. You were the one who introduced the quotation. It is up to you to either support it, or withdraw it.
Percy, would you say that Darwin's contribution was the synthesis of methodology, where he offered the best (at least so far) explaination of the mechanisms involved?