A third great fact, partly included in the foregoing statement, is the affinity of the productions of the same continent or of the same sea, though the species themselves are distinct at different points and stations.
Hirugarren egitate nagusia, aldez bederen azaldu dugunaren barruan doana, kontinente edo itsaso bereko ekoizkinen ahaidetasuna da, nahiz eta espezieak berak ezberdinak izan leku edo arlo diferenteetan.