And in this case, the individuals which secreted a fluid, in some degree or manner the most nutritious, so as to partake of the nature of milk, would in the long run have reared a larger number of well-nourished offspring, than would the individuals which secreted a poorer fluid; and thus the cutaneous glands, which are the homologues of the mammary glands, would have been improved or rendered more effective.
Eta kasu honetan, jariakin nolabait edo neurriren batean elikagarriagoa, esne-izaeratik zerbait zuena, zerien banakoek, luzera, ondorengo ongi elikatu gehiago haziko zituzten, jariakin eskasagoa zerien banakoek baino; eta horrela azal-guruinak, ugatz-guruinen homologoak direnak, hobetu edo eraginkorrago bihurtuko ziren.