Evolution by Means of Hybridization : Springer : 9789401183819 : 9401183813 : 01 Jan 1916 : As aPreface is in reality a Postscriptum, the author may be permitted to open it by mentioning omissions. The chief sin of omission he committed, is evidently the insuffident justice he did to the writings of Anton Kerner von Marilaun, who was - he wants to state this explicitly - the first to recognize fully the significance of crossing as the underlying cause of the origin of spedes. What else should apreface say? If the work is as condensed as the present one, it may perhaps suffise to repeat what Linnaeus said to Haller: Si quos in me vidisti errores, Tu sapientior haec ignoscas. . .. Quos plures apud me detegere potes, eo gratior ero, tum possum omnia corrigere vivus; post mortem non licet emendare propria opuscula. By which however the author does not consider himself bound to gratefulness for every kind of critidsm. He is f. i. very little impressed by the kind of criticism which calls it