July, 1921] 



THE SEEDLING OF PHASEOLUS VULGARIS 



351 



ferences between correlations for groups of bundles lying on the same side 

 and those lying on different sides of the nodal complex. 



(1) The correlation coefficients between primary double bundles and 

 number of bundles in the epicotyl, r pe , as set forth in the first section of table 

 3, are in part positive and in part negative in sign. For the most part they 

 can not be considered statistically significant. The average value of those 

 for trimerous seedlings is .0226 while that for dimerous seedlings is 

 + .0768. 



(2) For the correlation between the number of intercalary bundles 

 &amp;gt;and the number of bundles in the epicotyl, r; e , shown in the second section 

 of table 3, the coefficients are not in general certainly significant in com- 



TABLE 3. Coefficients of correlation between number of primary double bundles, number of 



intercalary bundles and total number of bundles at base of hypocotyl, 



and number of bundles in central region of epicotyl 



parison with their probable errors. Two of the ten are indeed negative in 

 sign. The coefficients for line 143 in both trimerous and dimerous seedlings 

 and possibly that for line 139 in the dimerous seedlings may be significant. 

 The fact that eight of the ten coefficients are positive suggests that there is a 

 slight relationship between the number of intercalary bundles at the base of 

 the hypocotyl and the number of vascular elements in the central region of 

 the epicotyl. The general average is +.0780 for the trimerous and +.0954 

 for the dimerous. 



This suggestion is only slightly strengthened by inspection of the two 

 sets of diagrams on which the regression equations are presented and drawn 

 with the empirical means. Diagram 3 pictures the results for trimerous 

 seedlings while the comparable representations for dimerous seedlings are 

 shown on diagram 4. These show that while the slope showing the change 

 in the number of bundles in the hypocotyl associated with variations in the 

 number of intercalary bundles at the base of the epicotyl is very steep, it is 

 practically nothing for the epicotyl, thus indicating a very close relationship 

 in the former case but the practical absence of interdependence in the 

 latter. 



