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AMERICAN JOURNAL OF BOTANY 



TABLE 2. Mean number of bundles at base of hypocotyl 



[Vol. 



We cannot, therefore, assert on the basis of the data now in hand whether 

 dimerous, hemitrimerous, and trimerous seedlings differ in the number of 

 intercalary bundles at the base of the hypocotyl. In so far as it goes the 

 evidence suggests that the hemitrimerous seedlings have a larger number 

 of int-rcalary bundles than the trimerous but a smaller number than the 

 dimerous plantlets. 



The means for total number of bundles (primary double bundles plus 

 intercalary bundles) at the base of the hypocotyl set forth in the third 

 section of table 2 show that in four of the five cases the mean number of 

 bundles is lower in the hemitrimerous than in the trimerous seedlings. 

 The differences are, however, very slight indeed and cannot in general be 

 considered significant in comparison with their probable errors. The 

 differences between the hemitrimerous and dimerous seedlings on the other 

 hand are rather large and in every case are unquestionably significant. 



Summarizing these results, we note that the hemitrimerous seedlings 

 are conspicuously differentiated from the dimerous seedlings in the number 

 of primary double bundles and in the total number of bundles. They are 

 less conspicuously differentiated, if at all, in number of intercalary bundles. 

 They are unquestionably differentiated from the trimerous seedlings by 



