118 Inheritance in the Cowpea 



Watson, Black Holstein, Black eye, Brown Solid, Brown Watson, Brown 

 Holstein, Brown eye, and White. The ratios between these types have 

 not been fully worked out, but it is clear that the factor for Dark 

 flower and Watson pattern, for Holstein, and also for Black, can be 

 carried by an albino type (white flowered and white seeded). 



The subject of colour correlation in the cowpea has been discussed 

 by Dr Spillman (1913). His note, however, is short, and does not con- 

 tain the experimental results on which his conclusions are based. Some 

 of his statements may, however, be discussed. According to him all 

 varieties having white or cream coloured seeds have white flowers and 

 are devoid of anthocyanin in stems and leaves. This is not always true. 

 In the cross Red Ripper by Para, a certain number of types in F^ have 

 white seeds and are devoid of anthocyanin in stems and leaves but also 

 have a distinct violet tinge on the wings of the flowers. 



He further states that the flower colour and the anthocyanin in 

 stems and leaves are dependent on two Mendelian colour factors : 



{a) The general factor for colour in the seed coat. 



(6) The special factor for black which when added to a variety 

 having coffee coloured seeds converts the seed colour to black. 



It has been shown in this paper that the factor for black affects the 

 seed coat, the pod tip, the calyx and the peduncle. It does not appear 

 to have anything to do with the flower colour or the factor which causes 

 anthocyanin to appear in stems and leaves, except that it is without 

 visible effect except in presence of such a factor. It is, of course, possible 

 that Spillman was working with a different factor for black, and all that 

 the present writer wishes to point out is that Spillman's conclusions are 

 not of universal application. 



Summary. 



1. In the preceding pages an account has been given of the mode 

 of inheritance of factors affecting the flower colour, pattern of the seed 

 coat, and colour of the seed coat pattern of Vigna sinensis. These 

 factors are : 



L. A factor which produces the type of flower colour known as 

 Pale. The factor has visible effect only in types with the Holstein and 

 Small eye patterns. It is very possibly the factor mentioned b}^ 

 Spillman (1913) as the one responsible for the production of anthocyanin 

 in stems and leaves. 



D. A factor which has no visible effect except in presence of L, 

 when it converts the Small eye pattern to the Watson pattern and the 



