270 SOME RECENT RESEARCHES IN PLANT PHYSIOLOGY 



these were of a tangible nature. Thus the albino or true 

 white contains neither apigenin nor luteolin. The ivory 

 contains apigenin and a factor, absent from yellow, which 

 inhibits the formation of luteolin, for ivory is dominant 

 to yellow. In addition to these there are eight varieties, 

 of which four are combinations of red anthocyanin with 

 one or other of the two flavones, and in four others the red 

 is replaced by the magenta. The complete list is given 

 below: 



7. Rose dore. 



8. Yellow tinged with crimson. 



9. Ivory tinged with magenta. 



10. Crimson. 



11. Magenta. 



1. White. 



2. Yellow. 



3. Ivory. 



4. Yellow tinged with bronze. 



5. Ivory tinged with rose -dore. 



6. Bronze. 



Of these, rose-dore is due to the combination of apigenin 

 with red anthocyanin, whereas the latter and luteolin yield 

 bronze. Crimson results from the presence of magenta 

 anthocyanin with luteolin, whereas with apigenin the 

 colour of the magenta is not appreciably altered. The 

 Mendelian relationship of the above varieties, from 4 to 11, 

 is concisely shown in the following scheme drawn up by 

 Wheldale. In it, those which are dominant have arrows 

 pointing in their direction. 



Magenta. 



Ivory tinged 

 Magenta. 



Ivory tinged 

 Rose-done 



Yellow tinged 

 Crimson 



Kose-dore 



Crimson. 



Bronze 



Fro. 26. 



Yellow tinged 

 Bronze. 



