ANTHOCYANINS AND GENETICS 177 



F, which regulates distribution of colour. Thus an individual hetero- 

 zygous for all three factors will give 



9 FRQ...full colour (magenta or crimson). 

 3 RQ ...Sirdar (magenta or crimson). 



3 Q faint colour (pinks). 



1 - - green (whites). 



Purplish-red in the stem is dominant to the true red of 'Orange 

 King,' and one factor only is necessary to produce the change. 

 Blue in the stem is recessive to all colours. 



No case is known of inhibition in the stem, that is, there is no domi- 

 nant green stem. 



Light shades in the stem colour (flowers light) are dominant to 

 deep shades (flowers light or deep). Probably one factor is concerned 

 with heterozygous forms, but there may be more. 



In some cases there is one factor between crimson and magenta; 

 other cases indicate two factors. 



It is doubtful whether there exists one or more diluting factors. 

 There is one factor diluting stem colour and another flower-colour, 

 and these are inherited independently. 



Factors (flowers}. 



Colour in flowers may be produced by two or more complementary 

 factors. 



The difference of one factor regulates the distribution of colour 

 between ' Sirdar ' and full colour, and also between pale and full colour 

 as in stems. 



Full colours are dominant to pale colours. 



Magenta is dominant to crimson. 



Magenta and crimson are dominant to full red ('Orange King'). 



Blue is recessive to all magentas and reds. 



Whites may be dominant or recessive to colours. 



Dominant whites are generally red-stemmed. A green-stemmed 

 white variety, 'Pearl,' is a dominant white (Keeble & Pellew, 541); 

 the same authors also report that a full red-stemmed white, 'Snow 

 King,' may be recessive. The flower is only white in dominant whites 

 if homozygous for the inhibiting factor. It has also been suggested 

 that suppression of colour is due to two inhibiting factors, central and 

 peripheral, one of which is represented in ' Duchess.' 



Keeble & Pellew (541) provide further results on dominant whites. 

 Hitherto all whites with red stems have been regarded as dominant 



w. p. 12 



