VOLUME XLVII 



NUMBER i 



Botanical Gazette 



JANUARY igog 



ON TRIPLE HYBRIDS 



Hugo de Vries 



Twin hybrids are produced when the pollen of Oenothera Lamarck- 

 iana or of one of its derivatives is crossed with the European sub- 

 species of O. biennis or of O. muricata. These twins appear in about 

 equal numbers and are constant in succeeding generations. One 

 of them, O. laeta, is broad and smooth leaved ; the other, O. velutina, 

 is more hairy and has furrow- shaped leaves. 1 



_ Triple hybrids may be produced by combining this phenomenon 

 with the hereditary qualities of O. lata and O. scintillans. Both of 

 them originated in my garden from O. Lamarckiana. O. lata is 

 female, its anthers are barren. O. scintillans is an inconstant species 

 which repeats its type only in one-third or two-thirds of its offspring. 

 Both of them, when pollinated by O. Lamarckiana, give a mixed 

 Progeny, only part of which is like the mother. 2 



In order to get triplets, therefore, we have to cross O. lata or O. 

 scintillans with some species which will split them into laeta and 

 velutina (as it would do O. Lamarckiana itself or some others of its 

 mutant species), and which, moreover, does not prevent them from 

 repeating their own type in their progeny. The triplets will then be 



• aeta, O. velutina, and O. lata. The first two will drop the special 

 c aracter of the mutant-parent (Box. Gaz. /. c. 403), but all three will 

 e intermediate hybrids between O. Lamarckiana or O. lata and the 

 species used as the other parent. 



com f ° Und that °' StHgosa R y db erg, O. Hookeri T. and G., and the 

 mon American subspecies of O. biennis L. comply with these 



1 Bot. Gazette 44:401-407. x 9 o 7 . 



3 ^e Mutations-Theorie. Vols. I and II. 



