On this same view of descent with modification, most of the great facts in Morphology become intelligible-whether we look to the same pattern displayed by the different species of the same class in their homologous organs, to whatever purpose applied, or to the serial and lateral homologies in each individual animal and plant.
Eraldaketadun ondorengotzaren teoria beraren arabera, Morfologiako egitate nagusi gehienak ulergarri bihurtzen dira, hala klase bereko espezie ezberdinek beren organo homologoetan zeinahi xedetarako garaturiko eredua dugula aztergai, nola animali edo landare-banako bakoitzaren alboko nahiz serieko homologotasunak aurkitzen ari garela.