HARRIS: TETRACOTYLEDONOUS RACE OF PHASEOLUS VULGARIS 24I 



If the plants be thrown into two groups only, as was done 

 above in the examination of cotyledon number, the results are: 



The differences are far larger than in the case of the cotyledons, 

 but the mean number of leaves on plants with normal or but 

 slightly broadened axes is so high that the results fully substantiate 

 the conclusions drawn above, that the approximate doubling in 

 the number of cotyledonary and foliar organs is not fundamentally 

 due to a broadening of the axis. 



If the seedlings be classified without regard to the structure of 

 the axis into those with and those without axillary shoots, the 

 results show that in both less and more mature series the plants 

 with the axillary shoots have a higher number of primordial 

 leaves. Thus: 



This is quite what one would expect from the fact that the simple 

 leaves of axillary shoots which seemed to have developed in the 

 seed were counted in the number of primordial leaves. The con- 

 stants show, however, that the difference is not large, amounting 

 on the average to less than a leaf in the two series considered. 



The fact that the excess in number of primordial leaves in 

 plants with axillary shoots is greater in the less mature than in the 

 more mature series, shows that there can be no considerable error 

 introduced by the counting of simple leaves of late development. 



With respect of size, form, and structure the leaves vary enorm- 

 ously. They range from those which are minute to those which 

 are far larger than the primordial leaves of normal plants. Length, 



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