120 Experiments with Primula sinensis 



in these two classes as compared with the corresponding classes with 

 green stigma ; on the other hand in the " Sirdar " classes the propor- 

 tions of green stigma and red stigma are slightly less than 3 : 1, but 

 further experiment is required before any suggestions can be made 

 as to any possible significance of these departures from normal distri- 

 bution. 



A further generation w^as raised by selfing one of the offspring of 

 the cross [" Duchess " x ^i (Dominant white x " Snowdrift ")]. The 

 most interesting point brought to light by this experiment is the fact 

 that there occur whites (? with no tinge) having red stigmas, but 

 without the central flush of deep colour which is characteristic of the 

 " Duchess" strain \ The numbers obtained were : 



Ked stem Green stem, red collar No colour in stems 



Duchess, White, White, White, 



red stigma green stigma red stigma green stigma 



4 16 5 19 



• Two with definite central tinge. 



t Three with definite central tinge. 



Tinged-whites with red stigma and without the central flush 

 occurred also among the offspring of a cross between " Duchess " and 

 the i^i of ("Ivy-leaf" X " Crimson King"). From this cross 31 plants 

 were obtained, 16 with green stigma, 15 red stigma. Those with green 

 stigmas were white or slightly tinged (like the F^ of "Dominant 

 white " X coloured, red stigma) ; those with the red stigma were deeply 

 tinged, but whereas some were of typical "Duchess" or "Buller" types, 

 others were without the deep central flush. 



The deep central flush of " Duchess" and "Buller" is therefore not a 

 necessary consequence of the absence of the factor inhibiting colour in 

 the stigma; it would appear rather that the character is an independent 

 one, but, like the deep spot of colour just external to the eye (p. 106), 

 is dependent for its full development on the presence of colour in 

 the stigma. We may surmise that the definite central tinge found in 

 some whites with green stigmas represents this character in combina- 

 tion with the green stigma. 



Green stigma in coloured flowers. The results showing the behaviour 

 of the green and red stigma in crosses between colours are : 



Number of families Green stigma Bed stigma 



4 315 116 



Expectation 323-25 107-75 



1 In Stellata flowers the "Duchess" flush is often only poorly developed, but the 

 phenomenon is of a different kind from that referred to here. 



