- Ornithischia, order Ornithischia - extinct terrestrial reptiles having birdlike pelvises: armored dinosaurs (thyreophorans); bone-headed and horned dinosaurs (marginocephalians); duck-billed dinosaurs (euronithopods)
--1 is a kind of animal order
--1 is a member of Archosauria, subclass Archosauria
--1 has members: