The Jack Russell Terrier is a white-bodied smooth, rough or broken-coated species of the dog. The Jack Russell is a broad type, with a size range of 10–15 inches (25–38 cm). It is an energetic breed of dog that relies on a high level of exercise and stimulation and it is also relatively free from serious health complaints.
Ronald Weasley's Patronus Charm takes the form of a Jack Russell Terrier. He used it during a Dumbledore's Army meeting in the 1995–1996 school year.