eb., 1921] 



HARRIS AND OTHERS SEEDLINGS OF PHASEOLUS 



75 



umber of primary double bundles at the base of the hypocotyl of trimerous 

 -lants is from 1.38 to 1.89 higher than in the dimerous controls. This 

 epresents an excess of from 30.5 to 47.0 percent. 



The five lines are not, however, consistent in the relative variability of 

 ; &quot;he normal and abnormal seedlings. 



The standard deviation of the number of primary double bundles in the 

 rimerous plants is lower than that in the dimerous plants in lines 75, 93, 

 nd 98. The differences are from 13.7 to 40.5 percent of the control values. 

 &amp;gt;ines 139 and 143 are in contrast to the foregoing. The trimerous plants 

 ,1 line 139 have a standard deviation of 0.323 .015 bundles, whereas the 

 limerous controls have a standard deviation of 0.140 .005, giving a 

 lifference of +.183 .016, which is 11.4 times as large as its probable error, 

 n line 143 the trimerous plants have a standard deviation of 0.581 .019 

 mndles as compared- with 0.315 .010 bundles in the normal controls, 

 jiving a difference of +.266 .021, which is 12.7 times as large as its 

 &amp;gt;robable error. These are relative differences of +130.7 percent for line 

 39 and + 84.4 percent for line 143. 



The same differences in variability between the lines is also conspic- 

 lous in the relative variabilities as measured by the coefficients of varia- 

 :ion. In the first three lines (75, 93, and 98) the coefficients of varia- 

 ;ion in the trimerous plants range from 4.9 to 7.3 percent as compared with 

 10.4 to 14.7 percent in the dimerous controls, giving differences in relative 



FABLE 5. Number of intercalary bundles at base of hypocotyl in trimerous and dimerous 



seedlings 



