HARRIS AND AVERY: MORPHOLOGICAL VARIATIONS 119 



RECAPITULATION 



This paper presents the results of a first attempt to determine 

 scne of the correlations in the structural variations of the seedling 

 OiPhaseolus vulgaris. 



The materials are drawn from a series of lines of Navy beans 

 giwn for the past several years at the Station for Experimental 

 Solution. The seeds used were harvested from plants of selected 

 ai:estry. Neither of these factors will, we believe, invalidate the 

 occlusions drawn in this paper. These conclusions will not neces- 

 saly apply to certain entirely abnormal races. 



Fasciation-like broadening of the axis and longitudinal division 

 of:he axis distal to the insertion of the primordial leaves are both 

 rcre frequent in seedlings showing separation of the cotyledons 

 ail in tricotyledonous seedlings than in those which are normal. 



Seedlings which are normal except for the separation of the 

 ccyledons and those which have three cotyledons and a normal 

 p;r of primordial leaves or three cotyledons and a whorl of three 

 pmordial leaves produce a larger number of leaves, a larger num- 

 b&amp;lt; of leaflets and a higher percentage of leaves with lobes at the 

 thd node than do those which are normal in their cotyledonary 

 ail primordial leaf characters. 



Seedlings which are tricotyledonous, with either a normal pair 

 oia whorl of three primordial leaves, show higher percentages 

 of/ariation in the axis, or the leaves produced by the axis, distal 

 tothe primordial leaves than do those which are normal except 

 fothe separation of the two cotyledons. 



These studies w r ill be continued. 



STATION FOR EXPERIMENTAL EVOLUTION, 

 COLD SPRING HARBOR, NEW YORK 



