114 Inheritance in the Cowpea 



the normal Sea Island type behaves as a simple dominant to the 

 Crinkled Dwarf Rogue. The latter type differs from normal Sea Island 

 in respect of almost every morphological character and also in certain 

 physiological characters. The whole plant is much smaller ; the leaves 

 have a crinkled and mosaic appearance and have ragged edges. Both 

 buds and bolls are shed much more easily than in Sea Island and there 

 is a general reduction in the size of all parts of the plant. 



In the case of the association of the red tip of the young pod with 

 the presence of black in the testa, and of coloration in calyx and 

 peduncle, it will be shown that this combination of characters as a 

 whole is allelomorphic to the absence of such a combination, i.e. to pod- 

 tip devoid of colour, seed devoid of black (in this case the colour of the 

 seed is brown), calyx and peduncle without red colour. This may be 

 explained by assuming that several completely coupled factors are 

 concerned, but it seems more reasonable to suppose that all these 

 effects are manifestations of a single factor, B. 



The Experimental Results. 



Cross 1. Black eye by Rounceval. 



Black eye. Black present in seed coat ; young pod with red tip, red 

 colour present in calyx and peduncle (B). 



Rounceval. Seed coat uniformly brown, immature pod, calyx, and 

 peduncle green {h). 



The F^ showed complete dominance of B. 



The F^ and F^ results. 



In Tables XIV and XV will be found the results of the F^ and F^. 

 Reference to these two Tables* will show that the ratio of B to h in 

 F2 is 3 — 1, that in F.^ all the families from F2 recessives bred true and 

 that of the families from F^ dominants 18 bred true, while 40 segregated 

 into B and 6, again in the 3 — 1 ratio. The ratio of pure to hetero- 

 zygous dominants is very close to the expected 1:2. 



To sum up : the two sets of characters comprised under the symbols 

 B and h, are allelomorphic to each other. 



(h) The Brown and Red colour of the Pattern of the Seed, Goat. 



In the cross Brown eye by Red, a study was made of the inheritance 

 of the colour of the seed coat pattern. The extent of the colour varies 

 with the extent to which pattern is developed. Thus in dealing with 

 Small eye types it is often impossible to separate different shades, 

 especially those which are even difficult to classify when the coloui' is 



