18 



BULLETIN 971, U. S. DEPARTMENT OF AGRICULTURE. 



most extreme form of the hairy Esperanza variety, where the tassel 

 consists of a single spike having many rows of clustered spikelets. 



The reduction of the branches of the staminate inflorescence in- 

 volved only those branches that were finally eliminated, while the 

 others remained unaltered. Thus, there was no general shortening 

 of all the branches, resulting in the complete reduction of the short 

 upper branches, but rather a definite change from branches to spike- 

 lets in the upper portion. This is illustrated in figure 6, where it is 

 seen that the form of the present normal inflorescence would be al- 

 most exactly that of the ramose inflorescence if the upper branches 

 of the ramose inflorescence were reduced without altering the re- 



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Fig. G. — Diagrams showing tassel conflguratioBS of the first-generation plants and the 

 normal and ramose segregates Oif the second-generation plants of Ramosa-Gordo maize 

 hybrids. The solid vertical line represents in each diagram the length of the central 

 spike, while the horizontal lines show the length of the lowest and the uppermost 

 branches. The dotted lines show the projected angles formed by the lowest and upper- 

 most branches. 



maining branches, while it is equally apparent that the central spike 

 of the Gordo variety has been elongated. 



CONCLUSIONS. 



The branched-ear variation designated Zea ramosa by Gernert 

 has behaved generally as a simple Mendelian character recessive to 

 the normal condition. In Gernert's variation the number of branches 

 in the staminate inflorescence are increased greatly, and the con- 

 figuration of the inflorescence is altered. This characteristic stami- 

 nate inflorescence has always appeared in conjunction with the 

 ramose ear, enabling the observer to detect the Ramosa plants in the 

 field before examining the ears. 



Crosses have been made between this ramose type and a type of 

 maize from Mexico called Gordo, which has very few tassel branches, 



