216 



Blakeslee. 



Table 3. 

 The Fs generation and Back-crosses with Crosses between Purple 

 Coned (P) and" Black Yellow Coned (BY) Rudbeckias. 



T. Inheritance of Red Yellow cones. 



The Red Yellows comprise the clones of V 83, V 85 and V91 (which 

 were the original plants found in the wild) as well as yellow segregates 

 derived from these plants. Tables 4 and 5 show that the Red Y^ellow 

 is inherited as a simple Mendelian recessive. The agreement with ex- 

 pectation is better than w^as the case with the Black Yellows. This 

 may be due in part to the fact that breeding work with Red Yellows 

 was begun several years later than with Black Yellows and at a time 

 when the sources of experimental error were more thoroughly appreciated. 



VI. Crosses between Black Yellows and Red Yellows. 



From the breeding experiments outlined in the foregoing paragraphs 

 it is apparent that Black Yellows and Red Yellows are inherited as- 



^) Five pedigrees without yellow cones have been omitted from this summary 

 since they likely arose from selfing of the pure purple female parent in the P^ generation. 

 They contained 10, 10, 12, 18 and 43 purple coned plants respectively. 



^) A cross and its reciprocal with respectively 30 and 2 purple coned plants have 

 been omitted from the summaries. Their lack of yellow cones cannot be due to selfing, 

 but probably may be attributed to some experimental error. 



