PLANT HYBRIDIZATION BEFORE MENDEL 169 



". . . among which the resemblance of a hybrid to one of its parents, 

 either to the father or the mother, is so marked and preponderating that 

 the agreement with the one or with the other is unquestioned." (ib., 

 p. 285.) 



Gartner recognized, as did the other hybridists of his day, that 



there was always a difference between the first and the succeeding 



generations, the former being uniform, the later ones variously 



splitting up. He made no distinction between the second and the 



other following generations, but simply says that the fundamental 



ground material of which the hybrid is made 



". . . behaves differently in the second and in the further stages of 

 breeding, where, on account of the different nature of the two factors 

 of the hybrids in the succeeding fertilizations, an altered, shifting, vari- 

 able direction in type-formation enters into the arising varieties." (ib., 

 p. 572.) 



He further says, concerning variability in hybrids of the second 



and succeeding generations : 



"other hybrids, and in fact the most of them which are fertile, present 

 from the seeds of the second and further generations, different forms, 

 i.e., varieties varying from the normal types, which in part are unlike 

 the original hybrid mother, or deviate from the same, now more, now 

 less." (p. 422.) 



His most definite statement, however, regarding what we call 



"segregation" is as follows : 



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

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

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

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

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

 and finally, here and there an individual more nearly reverted to the 

 original father." (ib., p. 422.) 



Gartner did not fail to recognize the fact of unusual vigor in 

 hybrids, although he does not distinguish as to the 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 cultiva- 

 tion." (ib., p. 526.) 



Gartner recognized at once the possibilities for agriculture in 



the fact of the increased vigor of hybrids, although, of course, he 



did not realize the fact that this increased vigor belonged only to 



a "hybrid" generation, as distinguished from Fo segregates. 



