If we look to rather wider intervals of time, namely, to distinct but consecutive stages of the same great formation, we find that the embedded fossils, though universally ranked as specifically different, yet are far more closely related to each other than are the species found in more widely separated formations;
Aldi zerbait luzeagoak, hau da, formazio handi beraren mailaketa ezberdin baina jarraikakoak kontuan hartzen baditugu, aurkitzen dugu haietan lurperaturiko fosilak, unibertsalki espezie ezberdintzat sailkatuak izan arren, elkarren ahaide hurbilagoak direla, formazio oso bananduetan idororikoak baino;