250 



Gates. 



We have seen that, judged morphologically, i. e. as regards the 

 extent of the colour pattern on the buds, the character R is dominant, 

 but judged physiologically, i. e. as regards the quantity of anthocyanin 

 produced by the plant, this character is usually at least, and probably 

 always intermediate between the parents, though not necessarily always 

 an exact intermediate. We have further found that back-crossing with 

 grandiflora and rubricalyx greatly decreases the depth of pigmentation 

 in the former case and increases it in tlie latter. The result is that the 



Fig. 15. Dwarf type in grandiflora X rubricalyx, ¥2. 



depth of colour is inherited in a quantitative manner, and is not a 

 simple matter of presence or absence. 



But the organism as a whole is still more intimately connected 

 with the development and variations of this pigment character. In 

 a previous paper (G.^tes, 191 i b, pi. 6.) I used numbers i — 7 to denote 

 the various degrees of pigment development in the buds of riibrinervis. 

 In that paper it was shown that these stages form a series which is 

 absolutely continuous, while a wide gap exists between the extreme 

 stage, 7, and rubricalyx. In the present paper (see table III, p. 236) 



