206 ANTHOCYANINS AND GENETICS 



(in which a certain number of colour factors are known to be involved) 

 termed reduplication (see p. 185). Another kind of relationship is 

 that existing in Matthiola (Saunders, 587) between the factors for hoari- 

 ness of the leaves and flower-colour In Stocks, as we have alreadv 



i/ 



seen, colour (anthocyanin) is due to the presence in the zygote of two 

 factors (C and R), and if either of these be absent, the plant is an albino 

 as regards anthocyanin. In certain strains of Stocks, the hoariness 

 of the leaves has been found to depend also on the presence of two 

 factors (H and K). Between these two pairs of factors there is a 

 certain relationship, viz. that the hoariness due to H and K is only 

 manifested when C and R are both present. Hence an albino may 

 contain both H and K, and may yet be glabrous because it cannot 

 contain at the same time both C and R. An anthocyanin form, on the 

 other hand, which is glabrous carries of course C and R, but can only 

 contain either H or K, and not both ; when it carries C and R, as well 

 as H and K, it is hoary and coloured. Thus a heterozygote in all 

 four factors would give on selfing : 



81 CRHK Red hoary. 



27 CRH Red glabrous 



27 CRK Red glabrous. 



27 RHK White glabrous. 



27 CHK White glabrous. 



9 CR ... ... Red glabrous. 



9 CH White glabrous. 



9 CK 



9 RH 



9 RK ... ... ,, 



9 KH 



o p 



L) V ... ... , , 



3T> 

 JL V * ^ } 



3TT 

 -1-L * 



3T7- 

 I *- y ) 



1 



... ... ,, 



Finally a relationship between shape and colour occurs in the 

 Sweet Pea (Bateson, 524). All those varieties with an erect standard 

 are 'bicolor,' that is, within the variety, the standard differs more or 

 less in colour from the wings; ex. 'Purple Invincible' and 'Painted 

 Lady.' Varieties, on the other hand, with a hooded standard have 

 wings and standard more of a uniform tint; ex. 'Duke of Westminster' 

 and 'Duke of Sutherland.' 



