Dreams don’t lend themselves to paraphrase. What generally survives into waking are disconnected bits that seem to have no coherent relation to each other; it’s the dream that connects them.

The same is true of Anne Carson’s prose poem “Red Doc>,” a sequel of sorts to “Autobiography of Red.’’ It brings the story of Geryon, a boy-sprite, or sometimes just a sprite, or just a boy, up into the present; sending him, now called G, on a northward journey with Sad, his lover, and Ida, his friend and mercurial helper.