356 



AMERICAN JOURNAL OF BOTANY 



[Vol. 8, 



in which the differences between the coefficients for the two classes of plants 

 are shown. 



The differences in this table are generally negative, thus indicating that 

 the correlations are lower in the trimerous than in the dimerous seedlings. 

 The exceptions are of some interest. 



L//Vf 98 



i! 



10 - 



9 - 



DIAGRAM 8. Regression of number of bundles in central region of hypocotyl on 

 number of bundles in central region of epicotyl. Empirical means represented by solid 

 dots for dimerous seedlings and by circles for trimerous seedlings. 



There are only 4 exceptions among the 15 correlations between th_ 

 numbers of vascular elements in the basal region of the hypocotyl and 

 in the central region of the hypocotyl, as shown in the upper section of the 

 table. These are without exception insignificant in comparison with thei 

 probable errors. There are 9 exceptions among the 20 correlations 



,e 



