Its skull was very different from "Diplodocus", suggesting a different feeding method. It had many fenestrae (openings) and thin bones. It had a wide muzzle filled with more than 500 teeth. They were replaced often: about every 14 days the whole set were replaced together. The jaws may have had a keratinous sheath, something like a wide beak. Its jaws were wider than the skull, and its teeth were placed far to the front.