feb., 1921] HARRIS AND OTHERS SEEDLINGS OF PHASEOLUS 85 



In variability as measured by coefficient of variation, the dimerous 

 slants exceed the trimerous throughout, conspicuously so in lines 75, 

 3, and 98. In their standard deviation, the dimerous also markedly 

 xceed the trimerous in these three lines, but in lines 139 and 143 the 

 rimerous plants slightly exceed the dimerous. 



FIG. 18. Percentage frequency distribution of total bundles in central region of 

 hypocotyl. 



D. Summary for Base of Hypocotyl. For the base of the hypocotyl, 

 therefore, it is evident that in total bundle number the trimerous seedlings 

 decidedly exceed the dimerous ones. The intercalary bundles alone (which 

 form but a small part of the total) tend to be more numerous in the dimerous 

 seedlings. 



