226 Inheritance in Dolichos lablab, L. 



vegetative parts to include the nodal regions of the stem. The cross 



St Vincent Bush by Vilmorin's Stringless may be represented thus : 



Parents St Vincent Bush Vilmorin's Stringless 



cR ^ Cp 



White seed Brown seed 



White flower White flower 



Green plant body Purple stipular hairs 



Fi CcRp 



Black seed 

 Purple flower 

 Purple nodes 

 Fi 9CR 3Cp 3cR Icp 



Black seed Brown seed White seed White seed 



Purple flower White flower White flower White flower 



Purple nodes Purple stipular hairs Green plant body Green plant body 



It is clear that the best classification of the plants cauld be effected 

 by examining the seed colour. The E2 of the cross Cp by cR would show 

 in respect of seed colour 9 black, 3 brown, and 4 white. In the actual 

 experiments all the plants could not be examined for this character, as 

 many matured too late. Of 77 plants which were white flowered, 33 were 

 brown seeded, and 44 white seeded. These numbers correspond exactly 

 with expectation on the basis of a 3 : 4 ratio. 



General Summary. 



In a cross between two varieties of Dolichos lablab the inheritance of 

 growth habit and distribution of anthocyanin pigmentation of flower, 

 seed, and vegetative parts have been studied. The Mendelian factors 

 which govern these characters are as follows : 



I. The factor for indeterminate habit. 



C. The factor for purplish brown seed coat and purple stipular hairs. 



R. A factor which has no eifect except in presence of C, when it 

 converts white flower into purple, brown seed into black, and causes 

 pigmentation of the nodal regions. 



REFERENCES. 



Bateson, W., Punnett, R. C, and Saunders, E. R. 1905. Reports to the Evolution 



Committee of the Royal Society, II. 

 Emerson, R. W. 1916. " A genetic study of plant height in Phaseolus vulgaris.'" 



Neb. A. E. 8. Research Bull. 7. 

 Habland, S. C. 1919. " Inheritance of certain characters in the cowpea." Journ. 



of Genetics, Vol. viii. No. 2. 

 Morgan, T. H., Sturtevant, A. H., Muller, H. J., and Bridges, C. B. 1915. 



The Mechanism of Mendelian Heredity. 

 Saunders, E. R. 1909. Cited in Mendel's Principles of Heredity, W. Bateson, p. 95, 

 Waby, J. F. 1917. Journ. Bd. Agric. British Guiana. 

 Whbldale, M. 1907. " Inheritance of Flower Colour in Antirrhinum majus.'^ 



Proc. Roy. Soc. Vol. lxxix. B. 



