So, again, several highly competent observers maintain that the existing productions of the United States are more closely related to those which lived in Europe during certain late tertiary stages, than to the present inhabitants of Europe; and if this be so, it is evident that fossiliferous beds now deposited on the shores of North America would hereafter be liable to be classed with somewhat older European beds.
Era berean, zenbait behatzaile oso gaik uste du egun Estatu Batuetan diren ekoizkinak lotura hertsiagoa dutela Europan tertziarioko azken aldietan bizi izan zirenekin, Europan egun bizi direnekin baino; eta hau horrela bada, bistakoa da Ipar Amerikako kostetan egun metatzen diren geruza fosildunak, gerora, Europako geruza zerbait zaharragoekin batera sailkatzeko arriskua legokeela.