E. R. Saunders 



369 



Fig. 1. 



Pig. 2. 



Note 3. On certain sap-colours not dealt with in the earlier 

 accounts, and on the constitution of the sulphur-white 



RACE. 



Sap-colours. 



Rose is obtained from unions where the colour factors C and R are 

 present together with a factor for paleness, provided the blue factor B 

 is absent from at least one of the parents. Hence it is obtained when 

 flesh or a certain type of sulphur-white (type 1 of p. 367) is crossed with 

 any form which gives a coloured jPj. If both parents lack B then it 

 appears in Fi , but if one or other contain B it does not occur till F,. 

 Thus when sulphur-white type 1 was crossed with red, flesh, cream, or 

 Brompton white, F^ was rose ; whereas when bred with azure or light 

 purple the rose colour only appeared in certain plants in F,. Owing 



