B.—CHEMISTRY. 47 
independently by Willstatter and by Everest ; incidentally their separate 
memoirs afford an unusual example of synchronous publication, each 
haying been communicated to the respective academies on the same 
day, March 26th. Willstatter identified phloroglucinol (1:3: 5-trihy- 
droxybenzene) as a common product of hydrolysing anthocyanidins with 
alkali, obtaining also p-hydroxybenzoic acid from pelargonidin, proto- 
catechuic (3: 4-dihydroxybenzoic) acid from cyanidin, and _ gailic 
(3: 4: 5-trihydroxybenzoic) acid from delphinidin. Accordingly he 
eckea for the anthocyanidin chlorides two alternative formulz, 
O.Cl 0.Cl 
HO 9 Ne \ex and HO et Yee 
ap ae NZ 
OH CH OHM GX 
in which X represents the substituted benzene ring which appears 
in the form of a phenolcarboxylic acid on hydrolysis. Later in the 
same year he confirmed (with Mallison) the former of these repre- 
 sentations a reducing quercitin to cyanidin chloride, 
OH q H 
PS LOG di 
p< 20 eo 
kid C.0OH DBF eet 
OH CO OH CH 
and (with Zechmeister) by effecting a complete synthesis of pelar- 
gonidin chloride, 
from 2: 4: 6-trihydroxybenzaldehyde. 
HKverest reached the same conclusion by recognising the significance 
of the fact that a flavone, e.g., luteolin, and a flavonol, e.g., morin, 
yield red pigments on reduction; he therefore reduced quercitrin (the 
rhamnoside of quercitin) to cyanidin, and rutin (the rhamnoglucoside 
of quercitin, and identical with osyritin, myrticolorin, and violaquer- 
citrin) to cyanin. Moreover, he showed that the petals of many yellow 
_ flowers, e.g., daffodil, wallflower, tulip, crocus, jasmin, primrose, and 
—— 
viola, or the white blossoms of narcissus, primula, and tulip, all yield 
red pigments on careful reduction, and in subsequent papers (e.g., 
with A. J. Hall, 1921) has indicated reduction of yellow sap-pigments 
belonging to the flavonol group as representing the probable course 
of anthocyan-formation in plants. In this connection it is noteworthy 
that an association between the pigments of sap and of blossoms was 
adumbrated in 1855 by Martens, who suggested that a faintly yellow 
substance in plant sap, when oxidised in presence of alkalis and light, 
produces the yellow pigments, and that these, by further oxidation, 
