Further Studies on the Apogamy and Hybridization of the Hieracia. 261 



as in the father. With regard to the fertile Fj individuals, they 

 produce an F, which is completely homogeneous and quite like the 

 parent individual of Fj; this must no doubt be attributed to the 

 apogamy. From another point of view, the origin of species by 

 means of. hybridization, we may be allowed to say that the cross 

 H. auricula x aurantiacum can give rise to new forms or 

 species, at once quite constant. 



5. H, excellens x aiiratifiacnin. 



a. As mentioned in my paper of 1906 (p. 239), in June 1904 

 I castrated some heads of the many-headed H. excellens (related to 

 H. magyarimm N. P.) and isolated others, and at the same time 

 pollinated some heads of another corymb of the same individual with 

 H. aurantiacum. The castrated and the isolated heads gave rise to a 

 new, apogamically developed generation, while the result of the 

 crossing w'as 20 individuals of pure H. excellens and 6 hybrids. These 

 6 were all different to one another, but the differences in characters were 

 almost always within the range of the characters of the two widely 

 different parents. Most prominent was the difference in sexuality; 

 the mother plant, H. excellens, is purely female, while the father 

 plant, H. aurantiacum, is hermaphrodite, and some of the hybrids 

 followed the mother, others the father. The characters of the 6 hybrids 

 can be described briefly in the following way: 



No. 461. Vegetative part comparatively weak, and development 

 of stolons much poorer than in either of the parents; hermaphrodite; 

 corolla pure yellow. 



No. 463. Vegetative part vigorous; very similar to the mother, 

 but more robust; female; corolla yellow as in the mother, but the 

 head a little larger and with dark, more hairy involucre. 



No. 463. Vegetative part vigorous; similar to the mother, but 

 more robust; female; corolla orange-yellow with a red stripe on the 

 underside and red teeth; head as in 462- 



No. 464. Vegetative part vigorous; rather intermediate; herma- 

 phrodite; corolla yellow-orange-red with red underside and red teeth; 

 head as in 463. (Figured in the paper of 1906 as fig. 5.) 



No. 465. Vegetative part weak; development of stolons rather 

 poor; hermaphrodite; corolla nearly as 464, perhaps a little nearer to 

 the father; quite sterile, died after first flowering. 



No. 46g. Vegetative part weak; leaves of the rosette narrower than 

 in the parents. Died in the winter of 1906 — 07 without any flowering. 



