Had it not been for the rare accident of the preservation of footsteps in the new red sandstone of the United States, who would have ventured to suppose that no less than at least thirty different bird-like animals, some of gigantic size, existed during that period?
Estatu Batuetako egungo harearri gorrian oinatzak kontserbatzea den kasualitate arraroagatik izan ez balitz, nor menturatu zatekeen pentsatzera hogeita hamar txori-antzeko animalia, gutxienez, tamainuz erraldoiak batzuk, existitu zirela aldi hartan?