• KAJMOSE IXFLOEESCEIfCE IJT MAIZE. 15 



It was found on a A'isit to Mr. Mack's gardens that the ramose 

 phints were not being recognized until the ears were harvested. Thus, 

 no selection was exercised against the ramose form of tassel except 

 in so far as the two forms of inflorescence were associated. The re- 

 sult appears to have been an unintentional separation of the ramose 

 ear from the characteristic ramose tassel. Even after 11 years of 

 selection ramose ears appear occasionally and in combination with 

 ramose tassels, but many more plants with typical ramose tassels and 

 unbranched ears are found. The most common type of plant has a 

 perfectly normal ear, while the tassel is intermediate between normal 

 and ramose. Several self-pollinated progenies have been grown from 

 these typical j)lants, and their pedigree is shown in figure 5. In a 

 population of 55 plants, 5 produced typically ramose ears while 2 

 bore ears with branches only at the base — 1 with an 8-rowed branch, 

 the other with the common 4-rowed branches. Thus, in the ap- 

 parently normal ears the ramose tendency may be manifested slightly. 

 These branched ears have little in common with the branched ears 

 developed in the Ramosa-Gordo hybrid, as they depart from the 

 normal unbranched form only by the few branches. They resemble 

 more closely a type of branching found in the Pawnee variety, and 

 frequently in other varieties, the resemblance being so close as to 

 suggest a relationship. The branched form of the Pawnee has re- 

 mained unstable through three generations of self-fertilization, al- 

 though the percentage of branched-ear plants has increased. The 

 small number of branched ears in these intermediate strains of Mr. 

 Mack's sweet corn seem to offer an entirely parallel case, and it may 

 be justifiable to conclude that the Pawnee type of branched ear is 

 simply a reduced stage of the ramose form. 



Whether the intermediate forms of Ramosa isolated from the 

 Ramosa-Gordo hybrid represent a series of multiple allelomorphs, 

 multiple factors, or modifying factors remains an unsolved problem. 

 The intermediate forms seem to be recessive to the typical Ramosa; 

 at least a cross between a plant having an ear with IT branches and 

 a typical ramose plant gave fully ramose plants in the first genera- 

 tion. On the other hand, the progeny of the self-pollinated inter- 

 mediate parent produced 11 ramose, C intermediate, and 2 unbranched 

 ears. Results of this kind are disconcerting from the standpoint of 

 simple analysis. About the* only conclusion possible at this time is 

 that true-breeding intermediate strains have been isolated having 

 unbranched ears. 



^Vhile man}' ears without branches are produced by the plants of 

 the Ramosa-Gordo hybrids, they nevertheless exhibit other char- 

 acteristics of their Ramosa ancestry which become more evident with 

 a study of the intermediate forms. The seeds are borne on pedicels 

 much longer than those of normal ears, and the abrupt taper with 



