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AMERICAN JOURNAL OF BOTANY 



larger series of plantlets would result in the finding of such seedlings in 

 lines 98, 139, and 143, thus bringing the five series into full agreement. 



In the trimerous seedlings the number of bundles shows rather wide, 

 and fairly symmetrical, distribution about the modal class, which is ig 

 bundles. The lines differ, however, to a considerable extent in the amount 

 of variation from the modal class. In lines 75, 93, and 98 the frequencies 

 are to a far greater extent concentrated into the modal class, which contauji 

 from 39 to 51 percent of the frequencies, than in line 143, which contaifc 

 only 24 percent of the cases. Line 139 is intermediate between these twi 

 extremes. 



For a more precise comparison we utilize the constants set forth in 

 table 1 6. 



TABLE 16. Statistical constants for number of bundles in epicotyl of trimerous and dimeroiu 



seedlings 



These results show that without exception the average number of bundl 

 in the epicotyl is .higher in trimerous than in dimerous seedlings. Tl 

 difference ranges from 2.8 to 3.7 bundles. The probable errors of the&amp;lt;&amp;lt; 

 differences are so small that there can be no reasonable doubt of ther 

 significance. In relative terms, the number of bundles in the abnorm 

 plant is from 23.0 to 30.3 percent higher than that in the normal plant. 



