14 BULLETIX 971, TJ. S. DEPARTMENT OF AGEICULTURE. 
branches to spikelets first took place on the lateral inflorescences, 
the terminal inflorescences undergoing alteration later. However, 
it can not be stated definitely that the reduction of branches of the 
staminate and pistillate inflorescences is due to completely inde- 
pendent genetic changes. The fact that the ramose variation as 
found had both inflorescences much branched and that they remain 
closely associated in most hybrids is an argument in favor of the 
hypothesis that the type of branching is constitutional with the 
plant and not restricted to particular inflorescences. If this were 
true, the ability to produce a highly ramified pistillate inflorescence 
on a plant with but little more than a normal number of branches in 
the staminate inflorescence would be attributed to genetic changes 
that have taken place since the original suppression of branches. 
In this connection it is of interest to note the experience of Mr. 
J. M. Mack, of Fall Brook, Calif., who for 11 years has been unsuc- 
cessfully attempting to eliminate the ramose type of ear from a 
variety of sweet corn. The ramose variation made its appearance in 
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Fig. o. — Diagram showing the pedigree of Mack's Yellow Evergreen sweet corn. 
Classifications marked with an asterisk ("*) are based on the ear characteristics ; 
most of the normal plants had intermediate tassels. 
Mr. Mack's stock in 1909. three years before its discovery by Gernert. 
Undoubtedly both strains originated independently, though crosses 
have proved them to be genetically identical. The seed of this sweet 
corn, used in experiments by the Office of Acclimatization and Adap- 
tation of Crop Plants, was received from the Office of Seed and Plant 
Introduction, United States Department of Agriculture, FHB No. 
23573, in March, 1917. Some of the plants grown from the seed in 
1918 were found to have typical ramose tassels (PL XIII), while 
others showed a well-marked intermediate stage (PI. XIV), the 
whole progeny with respect to the tassel falling into three fairly dis- 
tinct groups of 17 normal, 2 intermediates, and 2 ramose. When the 
ears were harvested it was found' that none of the intermediate or 
normal plants bore branched ears, and only one of the ramose plants 
bore a branched ear. but this was a typical ramose ear. The ears 
borne on the plants with intermediate ramose tassels showed no indi- 
cation of the ramose character, the rows being regular, the pedicels 
short, and the ears only moderately tapered. The intermediate tas- 
sels differ from those developed in the Eamosa-Gordo hybrids in that 
the only trace of Ramosa is the short central spike accompanied by 
the rather large number of branches (PL XIV) . 
