Gartner further states that when any two species, although most closely allied to each other, are crossed with a third species, the hybrids are widely different from each other;
Gärtnerrek, honez gain, dio, zeinahi bi espezie, hurbil-hurbilak izan arren, hirugarren espezie batekin gurutzatzen direnean, hibridoak elkarrengandik oso ezberdinak izaten direla;