862 Wisconsin Academy of Sciences, Arts, and Letters . 
for example, delphinidin hydrochloride and quercetin hydro¬ 
chloride, quercetin having an hydroxy group in the flavonol 
position. 
CH row 
The anthocyanin pigments have long been thought of as being 
of a quinoidal character. This supposition was encouraged 
by the oxidation of quercetin and chrysin, by Niernstein and 
Wheldale, 1 to quercetone and chrysone respectively, these oxi¬ 
dation products being “anthocyanin like.” Willstaetter and 
Everest 2 sought to explain the constitution of cyanin by assum¬ 
ing a quinoidal arrangement and classifying the anthocyanins 
as paraquinoidal flavone derivatives, as below: 
From such a molecule one would expect a hydroxy hydro- 
quinone as one of the products of abbau. Since no such pro¬ 
duct, but phloroglucine just as with the majority of flavone 
1 Ber., 44, p. 3487; 45, p. 499. 
* Amn., 408, p. 18. 
