Physiology of dinosaurs and that this was a feature they shared with birds. In 2007 Oliver Wings reviewed references to gastroliths in scientific literature and found considerable confusion, starting with the lack of an agreed and objective definition of "gastrolith". He found that swallowed hard stones or grit can assist digestion in birds that mainly feed on grain but may not be essential—and that birds that eat insects in summer and grain in winter usually get rid of the stones and grit in summer. Gastroliths have often been described as important for sauropod dinosaurs, whose diet of vegetation required very thorough digestion, but
Five Go to Demon's Rocks Lighthouse Game" (1985) was based on this novel. Five Go to Demon's Rocks Five Go to Demon's Rocks is the nineteenth novel in "The Famous Five" series by Enid Blyton. It was first published in 1961. Julian, Dick and Anne are coming to Kirrin to stay for a couple of weeks with their cousin, George (Georgina by rights), but Quentin's colleague Professor Hayling and his son Tinker (and monkey Mischief) arrive first. There isn't enough room at Kirrin Cottage for everybody to stay, so Tinker suggests he and the Five go to his lighthouse at Demon's Rocks up the coast.