440 



THE AMERICAN NATURALIST 



[Vol. LIII 



dition in general terms, of what we term segregation in 

 the second generation, is the following : 



Among many fertile hybrids, this eliaiifre in the second and succeed- 

 ing generations, alTects not only the flowers, but also the entire habit, 

 even to the exclusion of the flowers, whereby the majority of the indi- 

 viduals from a single cross ordinarily retain the form of the hybrid 

 mother, a few others have become more like the original mother parent, 



original farther (p. 422). 



Eegarding the matter of unusual vigor in hybrids, 

 Gartner remarks, giving examples, although again with- 

 out referring to any particular generation— 



The marked increase in the size of the flowers, is a phenomenon not 

 seldom occurring among hybrids (p. 295), and— 



One of the most marked and general characters of plant hybrids, is 

 the luxuriance of all their parts, since among very many of them, an 

 exuberance of growth and development of roots, branches, leaves and 

 flowers manifests itself, which is not encountered among the parents, 

 even under careful cultivation (p. 526). 



Gartner did not omit to apprehend the possible value 

 of this fact to agriculture, although, of course, he did not 

 recognize the first hybrid generation as a special phe- 



Among the characters of hybrids worthy of recommendation for agri- 

 culture, their tendency toward luxuriance in stalks and leaves, and 

 their extraordinary cai)acity for tillering is related al)ovo. With respect 



use of this characteristic ' { p! 6.34) . 



So far as genetics from the present technical stand- 

 point is concerned, Gartner's data of course are not of 

 special interest, because his crossing was made upon 

 species as units, and not upon the character-unit basis, 

 and no records were made of the numbers of the different 

 typos secured from his crosses. It is of interest to note, 

 however, that Gartner's methods in his hybridization 

 operations partially anticipated the rigorous methods of 

 to-day, regarding the ])urity of ])anMitnl types. 



■Mill..- the niunic <.f the types 



