OUR PRESENT KNOWLEDGE OF THE CHEMISTRY 

 OF THE MENDELIAN FACTORS FOR FLOWER- 

 COLOUR. 



PART II. 



By M. WHELDALE, 



Fellow of Newnham College, Cambridge, and formerhj Research Student 

 of the John Innes Horticultural Institution, Merton, Surrey. 



Since the appearance of Part I of the author's paper on this subject^ 

 further work on anthocyanin has been published by Willstatter, in 

 conjunction with Bolton, Nolan, Mallison, Martin, Mieg and Zollinger. 

 The present paper is concerned with the bearing of these later results 

 on the genetics of flower-colour. 



In Part I of the author's paper reference was made to Willstatter 's 

 first publication on anthocyanin" and the views contained therein, 

 namely, that anthocyanin is an oxonium compound, which is purple in 



1 Wheldale, M., "Our Present Knowledge of the Chemistry of the Mendelian Factors 

 for Flower-colour." Journal of Genetics, Cambridge, 1914, Vol. iv. (No. 2), p. 109. This 

 communication was delayed six months in the press, and at the time of writing, Willstatter's 

 second communication was not available and his third communication was not yet 

 published. 



The question as to the identity of the red products, formed artificially by reduction 

 from flavones, with natural anthocyanins is considered in a separate paper in this journal : — 

 Wheldale, M., and Bassett, H. LI., " On a supposed Synthesis of Anthocyanin." Journal 

 of Genetics, Cambridge, 1914, Vol. iv. (No. 1), p. 103. Owing to the above-mentioned 

 delay, the latter paper appeared first and as regards this particular question of identity 

 expresses the author's more recent views. 



- Willstatter's communications referred to are : — (1) Willstatter, E., und Everest, A. E., 

 "Ueber den Farbstoff der Kornblume." Liehigs Ann. Cliem., Leipzig, 1913, Bd. 401, 

 p. 189. (2) Willstatter, E., " Ueber die Farbstoffe der Bliiteu und Friichte." SitzBer. 

 Ah. Wiss., Berlin, March 1914, p. 402. (3) Willstatter, E. , und Mallison, H., "Ueber 

 die Verwandtschaft der Anthocyane und Flavone." SitzBer. Ak. Wiss., Berlin, July 1914, 

 p. 769. 



