SEED COAT COLOR IN GARDEN BEANS. 



77 



In the above table and the one following, represents the dark or Red 

 Valentine type of mottling, and o the Hght or Horticultural type. 



The behaiaor of "Wliite Marrow and Davis Wax in crosses with colored 

 beans indicates that both these varieties possess one or both of the factors 

 for mottling, as has already been shown (page 73). There is no evidence 

 that the factor, O, for dark mottling is present in either variety. Crosses 

 of these two varieties with Blue Pod Butter (Table V.) yield no dark mot- 

 tled beans, indicating that Blue Pod Butter does not possess the factor. 

 Therefore Blue Pod Butter may be described as PYzo, and the two white 

 varieties as pyZo or pYZo. All dark mottled varieties may be described 

 as PYZO. All other pigmented self-colored sorts used in these experiments 

 may be described as PyZO, except Warren, which is probably like Blue 

 Pod Butter so far as mottling factors are concerned. 



The results of crossing Wliite Marrow and Davis Wax with a number 

 of pigmented varieties are shown in Table VIII. A study of the results 



Table VIII. — Mottling Factors in White Beans. 



here shown indicates that the factor O just described is associated with 

 the Z mottling factor. If this be the case, on crossing a colored bean 

 PyZO with a white bean pYZo we should get in F2 a proportion of six 



