Wakeman—Pigments of Flowering Plants. 
821 
also in mahogany wood, and according to Gautier, 9 in various 
species of cahous, where he thinks there are several varieties of 
catechin of different melting points and characterized by a vary¬ 
ing carbon content. 
In a pure state catechin is composed of fine needle like color¬ 
less crystals, which by oxidation form dyes imparting yellow 
shades to textile fabrics. It is sparingly soluble in cold alcohol, 
readily soluble in hot alcohol. Air dried it dissolves in ethyl 
acetate, also to some extent in pure ether. Dried at 100° it 
is insoluble in both these solvents. In aqueous solutions lead 
acetate gives with catechin a colorless precipitate, ferric salts 
give a green color. In the presence of sodium acetate ferric 
chloride gives with catechin a deep violet coloration. 
The more important of the contributions to the chemistry of 
catechin are included in the following list: 
Literature on Catechin. 
Clauser, — B., 36, p. 101. 
Dellfs, — Pharm. CentrL, (1846), 604; Berz. Jahresb., 27, 
p. 284. 
Doebereiner, — N. Jahresb. d. Chem. u. Pharm., (1831), p. 378; 
Berz. Jahresb., 12, p. 250; Schweigg. Jr., 61, p. 378. 
Etti, — Monatsh., 2, p. 547; Wien, akad., 84, p. 553; A., 186, 
p. 327. 
Gautier, — C. r., 85, p. 342; 86, p. 668. 
Hagen, — Ann., 37, p. 320. 
Hlasiwetz, — Ann., 134, p. 118. 
Kostanecki and Lampe, — B., 39, p. 4007, 4014, 4022; 40, p. 720. 
Kraut and Delden, — Ann., 128, p. 285. 
Liebermann and Tauchert, — B., 13, p. 964. 
Loewe, — Zeit. anal. Chem., 13, p. 113. 
Ness van Esenbeck, — Ann., 1, p. 243. 
Neubauer,—Ann., 96, p. 337. 
Perkin, — Jr. Chem. Soc., 81, p. 1160; Proc. Chem. Soc., 20, 
p. 177. 
Schuetzenberger and Bach, — Bull. Soc. Chem., 4, p. 51. 
Swanberg, — Ann., 24, p. 215. 
Waekenroder, — Ann., 37, p. 306. 
Zwenger, — Ann., 37, p. 320. 
®C. r., 85, p. 342 ; 86, p. 668. 
