The turnip story ("How I edited an Agricultural Paper Once") appears in _Mark Twain at the Buffalo Express_, and also in Lou Budd's anthology--I, too, have no recollection of potatoes, unless he incorporated a story like that in _Following the Equator_. It's been a while since I read this, but it was an eclectic collection of set pieces along with his descriptions of the places he visited, and included the Pudd'nhead Wilson's New Calendar...best of luck in researching this. Jan McIntire-Strasburg