R. P. Gregory 107 



not fully developed unless the stigma is coloured ; nor, even if the stigma 

 be coloured, are they developed in plants which have the white eye of 

 the "Queen Alexandra" type (Plate XXX, fig. 11)'. Again, the spots 

 are deeply coloured only in deeply coloured flowers, their appearance in 

 flowers of a light shade somewhat resembling that which they assume 

 in plants with green stigmas. The limitation imposed in these cases 

 results from the dominance of an inhibiting character. There are also 

 limitations due rather to tlie lack of a coloured base ; the spot is not 

 visible in pale-coloured flowers, nor again in the flaked patterns of 

 full colour, unless it should happen that the colour is distributed in 

 any of the petals in a wide stripe covering the area occupied by the 

 spot. Such petals exhibit the spot, which may not be visible in other 

 petals of the same flower. 



Plants in which the development of the spot of deep colour is inhibited by the factor 

 for green stigma have flowers of a definite type, characterized by the presence of a 

 well-defined brownish spot. The character is a different one from the diffuse brownish 

 band which appears in some plants as the flowers fade (Plate XXXI, figs. 54, .55), and is 

 very clearly marked in the young flowers (Plate XXXI, fig. 50), becoming less conspicuous 

 as they grow older (fig. 51). This "ghost" of the spot is well seen in the F^ from 

 ("Crimson King " x " Rosy Magenta"), and in the Fa all the plants with red stigmas 

 have the spot of deep colour. The inheritance of the character is further illustrated 

 in the subjoined experiments in which a series of F2 pale pinks were crossed with 

 " Orange King." 



Green stigma Red stigma 



No spot Spot No spot 



— 9 — 

 _ 8 3 



— 6 3* 



No plants 



— 4 1 



7 — — 



No plants 



* These three had light stems, and a brownish marking in the region of the spot 

 somewhat resembling the marking which represents the spot in plants with green 

 stigmas. 



1 In plants with the large yellow eye the spot is pushed outwards, so that it occupies 

 the same position relative to the eye pigment as it does in the usual type (see Bateson, 

 loc. cit. Plate VI, figs. 19, 21). 



8—2 



