An extra-toes cat isn't a breed. It's any cat born with polydactyly, a harmless genetic variation that adds toes to one or more paws. The trait is dominant, so one affected parent can pass it on, and it turns up in domestic shorthairs and longhairs of every color and pattern. Most weigh 6 to 15 pounds and live 12 to 18 years.
The "Hemingway" nickname comes from writer Ernest Hemingway, who was given a six-toed cat named Snow White. Personalities are as varied as any cat's, so a polydactyl might be a bold greeter or a shy window-sitter. The main care difference is nail trimming, since extra claws can curl into the paw pads. Shedding is moderate, so a weekly brushing keeps the couch manageable.