Karen Russell’s new collection, Orange World, contains eight stories whose weirdness rests largely in their premises. “Bog Girl: A Romance” is a love story about a teenage boy and the girlfriend he finds preserved in a peat bog; “The Tornado Auction” concerns storm ranchers who breed prize twisters, funnel clouds, dust devils, and waterspouts; “Madame Bovary’s Greyhound” focuses on the tragic heroine’s once-enthralled, now blasé canine, beset by a trickle-down version of his owner’s sexual boredom. In capsule form, Russell’s stories pass among readers like gossip or jokes or memes; some of them have become famous for the kernel of tall tale or urban legend they contain.