Wakeman—Pigments of Flowering Plants. 865 
shaped crystals of a high melting point and a bright red color. 
The crystals dried in masses of a brownish color with a beauti¬ 
ful green reflection. This substance was no glucoside. If it 
existed as such in the plant, it was hydrolized in the process of 
preparation by the sulphuric acid used to decompose the lead 
precipitate. The crystalline substance was insoluble in ether, 
chloroform, hydrocarbon oils, and carbon disulphide, almost in¬ 
soluble in hot water and in 95 per cent alcohol, but easily soluble 
in 60-70 per cent alcohol when heated. It was possibly the 
pelargonidin sulphate described by Willstaetter. 
This compound gave a yellow acetyl derivative when heated 
with acetic acid anhydride and anhydrous sodium acetate. This 
acetyl derivative, computed upon Griffith’s formula of C 15 H 10 Q 67 
contained five acetyl groups. This, interpreted in the light of 
Willstaetter’s formula would probably mean that the sulphate, 
in the process of aeetylimtion, was changed to the acetate and 
that all four of the hydroxy groups were acetylized. When 
heated in alcoholic solution with zinc and acetic acid the red 
color of the crystalline pigment disappeared leaving a colorless 
solution. This, after standihg exposed to the air, gradually 
became deep red in color. No crystals could be induced to 
separate from this red solution. 
Willstaetter criticises severely the old method of attempting 
to separate anthoeyanln pigments by precipitation with lead 
acetate. However just this criticism may be when applied to 
anthocyanins in general the writer will not venture to say. The 
above described pigment, however, was easily obtained, appar¬ 
ently in a pure condition, by precipitating an aqueous extract 
of fresh geranium blossoms with lead acetate and decomposing 
the precipitate with sulphuric acid. The exact details of the 
process need not be given here. 
In 1911 Grafe 3 isolated what he considered as two pigments 
from the scarlet geranium, one glueosidal and the other not 
glucosidal in character. Willstaetter says that as a matter of 
fact both of Grafe’s pigments are glucosides, and that only one 
is present in the plant, the second being a mixture of the pig¬ 
ment with other substances. 
Willstaetter’s pelargonidin was separated in the form of the 
oxonium salt of the glucoside pelargonin. This upon hydroly- 
8 SitzungBtoer. d. Wien Akad, Wiss. math. nat. ki, 120, p. 765. 
55—S. A. L. 
