One dragon was said to have nine sons, each of whom had his own special talent. One, a turtle named Baxia, could carry heavy loads. Turtle tablets, which were stone tablets with bottoms that looked like turtles, appeared in the Han and Tang dynasties. The stone tortoises under their shells would strain their necks upward, with big eyes and open mouths.
龍生九子，各有本領，其中一子「霸下」，能負重，漢、唐時代，就出現了上碑、下龜的龜趺造型，石龜由甲殼下揚起頸子，巨目咧口，四足撐地，力托千斤，碑上則記載功績聖德，今天台南延平郡王祠還有九座龜趺，成為遊客爭相拍照之處。