When such varieties returned to their ancient homes, as they would differ from their former state in a nearly uniform, though perhaps extremely slight degree, and as they would be found embedded in slightly different sub-stages of the same formation, they would, according to the principles followed by many palaeontologists, be ranked as new and distinct species.
Aldakiok beren antzinako lekuetara itzultzean, lehenagoko beren egoerarekiko alde berdintsua, nahiz eta beharbada txiki-txikia, izanen luketenez, eta formazio bereko azpimaila ez hain ezberdinetan lurperaturik aurkituko liratekeenez gero, palentologo askok onarturiko hastapenen arabera, espezie berri eta ezberdintzat sailkatuko lirateke.