RAMOSE INFLORESCENCE IN MAIZE. 



30 



;iS 



SECOND GENERATION. 



The ears of the first generation and, for that matter, the normal 

 ears of the second generation provide no very good characters for 

 a quantitative comparison with the parents, since the branches are 

 suppressed. The pLants of the second generation were grown from 

 self-pollinated F^ seed. No difficulty was encountered in classifying 



them as to their ra- 

 mose or normal na- 

 ture from the stand- 

 point of the tassel, 

 and although it was 

 apparent that the 

 ramose tassels were 

 variable, the conical 

 configuration left no 

 ground for reason- 

 able doubt. Both the 

 normal and the ra- 

 mose segregates of 

 the second genera- 

 tion showed the ef- 

 fect of hybridiza- 

 tion, behaving in a 

 manner entirely 

 comparable with 

 that commonly ex- 

 pected in size char- 

 acters (fig. 2). Al- 

 though the normal 

 and ramose segre- 

 gates of the second 



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Pig. 1. — Frequency distributions with respect to the cen- 

 tral spike index in malzo plants of the Ramosa and 

 Gordo varieties and of the first generation of this hybrid. 

 Polygon at left, Ramosa ; at right Gordo ; inclosed in 

 broken line, first-generation hybrid. 



generation were 

 easily distinguished, 

 it is apparent from 

 the measurements in 

 Table I that the tas- 

 sels of the ramose plants are not, on the average, as ramose as those of 

 the Ramosa parent, and likewise the tassels of the normal plants are 

 not as extreme in form as those of the Gordo parent. This is shown 

 graphically in the central spike index in figure 3. In each case the 

 alterations are in the dire<?tion of the F^. Thus the ramose character, 

 while behaving in a general way as a unit in inlieritance, is capable of 

 being resolved into several parts which behave in inheritance as mul- 

 tiple-factor size charactei's (Table T). The counts, based on the con- 

 figuration of the tassel, gave 130 ramose and 399 normal, or 24.G±1.3 

 per cent ramose. 



