No. 628] VON GARTNER AND PLANT HYBRIDIZATION 435 



Mendel's data made it possible to precipitate into a defi- 

 nite morphological theory. Gartner went so far, how- 

 ever, as to attempt to measure this ''potency" in a defi- 

 nite manner, by means of the number of viable seeds pro- 

 duced in reciprocal crosses. 



That this relation of the factors of the fertilization forces in the case 

 of species of plants capable of hybridization, is definite and according to 

 ■law, we assume from the fact that from such a hybrid combination come 

 more or fewer good seeds to be sure, according to the favorableness or 

 otherwise of the incidental circumstance, but that, however, in the case 



bination of that kind (p. 206). 



Gartner goes so far as to say: 



The inequality in the strength of sexual affinity ( Wahlverwandt- 

 schaft), in the case of the reciprocal combination of species, is a gen- 



the disclosure of the relations, and to a closer determination of the 

 value in respect to magnitude of the individual factors of sexual affinity. 

 This inequality establishes a scale of sexual affinity peculiar to each 

 species, which lies in the difference in the relationship of the strength of 

 the two factors. In this singular characteristic of plants, the peculiar 

 nature of the si)ecies is most plainly recognized, — much more, in fact 

 than in its external form (p. 200). 



Those species which are able in crossing, to exert a 

 preponderating influence upon other species, Gartner 

 calls "generic types." 



Just as such ,o(Mu.rir types in hybrid broodin,-. nre iible. as it were, to 



and form of these species l)r()ken'and overmastered by others (p. 290). 



This manifestation of generic types, according to which one species 

 acts in a predominant manner over several other species in hybrid 

 breeding, is a further uncontradictable proof, that the relationship of 

 the forces, through which the union of two pure species takes place, 

 must be unlike, nn.l tlmt thore can he no question there of any balance 

 of factors. To l.o sure in mixed liyhrid<. ihe relationship of the forma- 

 tive forces of tlie Uvo sexual suhstrnia appears to be tolerably alike; 



character of the one, now that of the other factor is mire plainly ex- 

 pressed (p. 290). 



Gartner seems to see in this dominance of type in 



