Oh, nevermind. The story, found in the archives of Yale’s Beinecke Rare Book and Manuscript Library, is about life in Paris during the first World War. (And it’s more of a “cut-and-paste” job than a story, scholars suggest.)
I guess we’ll have to keep waiting for someone to dig up more than a fragment from Wharton’s unfinished work, Beatrice Palmetto, which includes a very un-Wharton-like sex scene between two characters who may be father and daughter.