MUTATIONS, VARIATIONS, AND RELATIONSHIPS OF THE OENOTHERAS. 27 



The original measurements upon which the above figures and conclusions 

 are based are presented in the form of correlation tables in figs. 7 and 8. A 

 comparison of the tables with the corresponding figures for 1904 shows that 

 those representing 0. lamarckiana are very much alike in the two years, the 

 degree of correlation being even higher in the latter year than before, due in 

 part possibly to the slightly greater heterogeneity already pointed out in the 

 cultures at the Station for Experimental Evolution. On the other hand, in 

 Oenothera ruhrinervis the corresponding tables for the two years are entirely 



35 



40 



45 



50 



55 



60 



65 



70 



20 25 30 



Fig. 6. — Comparison of the ratio between leaf-length and leaf-width in Ucnolhcra 

 lainarckijua (broken curve) and O. rubrinervis. 



different, as would be expected from what has already been said. In this 

 species the cosfficient of correlation has bsen considerably lowered. 



The coefhcients of correlation for the two species for the two years may 

 be compared in the following table: 



