172 ANTHOCYANINS AND GENETICS 



invariably associated with a low degree of pigmentation in stems and 

 rosettes. Moreover, the segregation of the rubricalyx character was not 

 found to be a simple Mendelian case. Shull maintains also that certain 

 of Gates' conclusions are erroneous, viz. that the rubricalyx character 

 represents a quantitative difference, and that it can be expressed by one 

 factor. 



The other case of interest in connection with anthocyanin is that 

 considered by Davis (592, 604) in connection with the stem coloration 

 (the formation of papillae or glands coloured with anthocyanin at the 

 base of long hairs) in parents and hybrids of crosses, 0. grandiflora 

 x biennis, 0. franciscana x biennis and their reciprocals. Davis con- 

 siders this character to be dominant to the green stem, but it has 

 not been shown to segregate in a Mendelian way. 



Oxalis. Nohara (635) worked with varieties of the so-called Oxalis 

 corniculata L. which differed from each other in the presence or absence 

 of purple (anthocyanin) in the eye of the corolla and in the leaves. 

 The presence of anthocyanin was found to be dominant to its absence, 

 and the intensity of pigmentation in Fj from pigmented by unpigmented 

 was found to be intermediate. The purple colour in eye and leaf is 

 due to one factor so that eye- and leaf-purples are associated, but the 

 leaf-purple can appear without the eye-purple. 



Papaver somniferum. De Vries (474) and Hurst (502) have shown 

 that the basal patch on the petals is dominant to its absence. Hurst 

 (502) also states that colour in the rest of the petal is dominant to 

 albinism, and that purple is dominant to red. 



Papaver Rhoeas. Shull has published work (588) on this genus. 

 It was found that varieties with a white margin were dominant to 

 varieties without the margin, i.e. the type. Certain whites crossed with 

 some reds gave white or striated offspring, but the same whites were 

 found to be recessive to pink or orange. Some red-flowered varieties 

 crossed together gave whitish offspring. Two suggestions are made: 

 (a) that only spectrum red is inhibited ; (6) that two factors are necessary 

 for inhibition. 



Phaseolus multiflorus. The characters which have received most 

 attention in this genus are those concerned with the pigmentation of 

 the seed-coat. 



Lock (504) made some preliminary experiments by crossing a dark 

 purple-seeded bean with a dark yellow-seeded bean. The F x was dark' 

 purple. The F 2 could be subdivided into two groups: (A] containing 

 beans of various shades of purple; (B) of various shades of yellow. 



