Concise hierarchy
	(Kingdom) Animalia - (Phylum) Chordata - (Class) Reptilia - (Order) Ornithischia
Subsequent positions
Current position
	Alternative positions
	
		Historical positions
		
			
				| †Ornithischia (Order) Seeley, 1887 | Ref: 
						
							1998 | 
				
					| †Ornithischia (Order) Seeley, 1887 | Ref: 
							
								D. Lambert & the Diagram Group, 1991(1997): 109. | 
					
						| †Ornithischia (Order) Seeley, 1887 | Ref: 
								
									P. Uetz, [1995-]1996: 30 Dec 1996. | 
						
							| †Ornithischia (Order) Seeley, 1887 | Ref: 
									
										1995 | 
							
								| †Ornithischia (Order) Seeley, 1887 | Ref: 
										
											R.L. Carroll, 1988: 622. | 
								
									| †Ornithischia (Order) Seeley, 1887 | Ref: 
											
												A.S. Romer & T.S. Parsons, 1986: App. 1 (p. 623). | 
									
										| †Eurypoda (Minorder) Sereno, 1986 | Ref: 
												
													P. Sereno, 1986: 252.
												 [new position] | 
										
											| †Ornithischia (Order) Seeley, 1887 | Ref: 
													
														T.I. Storer et al., 1979 | 
											
												| †Ornithischia (Order) Seeley, 1887 | Ref: 
														
															B. Grzimek et al., 1973 (1971): 596. | 
											
											Number of Subtaxa