THE PURE LINE 



105 



of selection for six years in pure line I as shown in 

 the accompanying table and in Figure 35. 



It is evident, for instance, that in 1907 the smallest 

 beans, weighing an average of 56 eg., gave an average 

 progeny weighing 69.07 eg, while the largest ones 

 for the same year, weighing an average of 81 eg., 

 produced nearly the same average in their progeny 

 as did the smallest beans, that is, 67.66 eg. 



Incidentally all the progeny from both large and 

 small parents averaged notably less in 1904 than all 

 the progeny from large and small parents in 1906, 

 a result due to a "poor year" when certain factors 

 of environment were unfavorable. Such unfavor- 

 able conditions, however, are known to influence in 

 no way the hereditary qualities of the beans. Thus it 

 appears that, although the progeny of a pure line 

 present plenty of variations of the fluctuating type, 

 due probably to environmental differences in nutri- 

 tion, moisture, etc., such variations are quite inef- 



