A supposed figure in the Glastonbury Zodiac, perhaps serving as its guard. It is, in fact, regarded as an extra-zodiacal sign. It has been given its name after a dog so called in a Somerset wassailing song. The dog star Sirius is supposed to be above the Girt Dog's nose. Its tale is at a place called Wagg. Mary Caine has argued that the Girt Dog may have been the prototype of the Questing Beast.