and secondly (in the following chapter), the wide distribution of fresh water productions; and thirdly, the occurrence of the same terrestrial species on islands and on the nearest mainland, though separated by hundreds of miles of open sea.
gero, hurrengo kapituluan, ur gezatako ekoizkinen banakuntza zabala aztertuko dut, eta, ondoren, lehorreko ekoizkin berberen presentzia irletan eta lehorralde hurbilenean, ehundaka miliatan itsaso zabala bitartean izan arren.