SEED COAT COLOR IN GARDEN BEANS. 95 



small numbers, indicating that these parents possess no determiners in 

 common. One plant \vith red mottled beans yielded in the next genera- 

 tion red mottled and buff beans in the proportion of 3:1, indicating that 

 the parent plant was heterozygous for the factors M and D. Red Valen- 

 tine X Giant Stringless gives results of the same nature, and they indi- 

 cate the same constitution as that of Golden Eyed Wax. In one cross of 

 these two varieties, dark red and even black beans appeared. This is so 

 contrary to the usual experience that it is thought they are due to acci- 

 dental crossing in the field, or some other accident of similar nature. 



In crosses of Red Valentine with Burpee Stringless we have coffee 

 brown, yellow and light red mottled beans, as would be expected from 

 the formulae already advanced. Buff beans also appear in small numbers, 

 indicating that these two varieties have no determiner in common. Dark 

 red mottled beans appear in numbers greater than those of light red 

 mottled beans, and so distributed as to make it doubtful if they are the 

 result of accident. Their presence can be explained on the supposition 

 that Burpee Stringless carries the determiner E. Small numbers of olive- 

 brown, or H, beans appear as in other similar crosses. The constitution 

 indicated for Burpee Stringless is PTyZMm'FCEd, which is in harmony 

 with the one previously advanced. 



Dark red mottled beans have been extracted from crosses of Red 

 Valentine with Prolific Black Wax, indicating that Prolific Black Wax 

 carries the alkaline determiner E. This type, self-fertilized, yields dark 

 red mottled and light red mottled beans in the proportion 25:12, probably 

 a simple 3:1 ratio. Buff beans also appear in small numbers, indicating 

 that these two sorts have no determiner in common. Coffee brown, or 

 F, beans appear in considerable numbers, and when selfed sometimes 

 breed true, or may yield yellow (C), buff (B) and olive-brown (H) beans 

 in proportions subordinate to the coffee brown. In this as in other crosses 

 involving Red Valentine, the parent type, light red mottled, always 

 breeds true when extracted. 



Warwick has a coat color apparently very similar to or identical with 

 Red Valentine. The blossom color is light pink, while the usual strains 

 of Red Valentine are white. This indicates a different pigmentation for 

 the two varieties, which may or may not affect the color of the seed coat. 

 When crossed with Challenge Black Wax, Warwick gives in the Fi genera- 

 tion a mottled bean showing black and red similar to those where Red 

 Valentine is involved. In later generations there is a greater complexity 

 among the mottled beans. Coffee-brown and yellow beans are extracted, 

 also the buff, or B beans, all in rather small nimabers. These solid-colored 

 beans all breed true or yield other hypostatic or recessive colors in com- 

 paratively simple proportions. Among the mottled beans various shades 

 of black, violet, brown, red and yellow may be seen, and in addition the 

 buff color always showing in mottled beans. Beans of these complex 

 colors segregate into self-colored beans or mottled beans of less complex 

 natures. We have observed no case where a mottled bean showing colors 



