I am ashamed, truly a-shamed I tell ya, that I cannot run down at least the first of these stories.
Story 1: Elderly colored couple dress as for church and begin a drive in their Model T. The dialogue and purpose is peculiar until the man drives them off the levee into the river, where they drown - it was all about a deliberate double suicide. Faulkner?
Story 2: (Which I seem to remember being by an American great like Faulkner, a very strange story for them to have written). A young teenaged boy compounds an elixir or compound that turns his sister into a chicken, and then back again. The only detail I can remember is the girl looking into a mirror and saying, “Boy, I am some ugly chicken, though.” Not sure if the events are real or imagined.
I have no idea, but at least this post will raise your thread. Have you tried looking at the full list of all 125 Faulkner short stories, in case you recognize a title?
Of course, but I haven’t found a good linkage of titles to summaries (or copies; I suspect many of the works are out of copyright now). Many of the titles sound “sorta right” but none of those I’ve been able to follow up on were correct.
I would have read both these stories in the early 1970s, while my mother was finishing her degree in Lit and there were many interesting books laying around.