Waheman—Pigments of Flowering Plants. 905 
Willstaetter 2 it is isomeric with carotin, the formula of each be- 
ing C 40 H 66 . 
Xanthophyll 8 (C 40 H 56 O 2 ) is probably referable to a hydro¬ 
carbon of this degree of saturation. It appears to accompany 
chlorophyll and carotin. Xanthophyl crystallizes in yellow 
crystals. It is easily soluble in acetone but difficultly soluble in 
petroleum ether and easily affected by light. 4 Whereas carotin is 
easily soluble in petroleum ether, difficulty in acetone, and is 
unaffected by light. 
Other studies of Carotin have been made by Hansen, 8 
Tschirch,® Sehunck 10 and Tsweth. * 11 
PIGMENTS REFERABLE TO HYDROCARBONS OF THE DEGREE OF SAT¬ 
URATION C n H 2n - 34 . 
One pigment of known constitution falling under this degree 
of saturation has been isolated. This pigment is dichrysorobin, 
referable to di (methyl-dihydroanthracyl.) 
* Zeit. Physiol. Chem.» 64, p. 47. 
* Czapek, Biochemie der Pflanzen (1913) I. p. 683. 
* B., Bot. Ges., 22, p. 414. 
•Site, her. phys. med. Ges., Wuerzburg (1888). 
* B. Bot. Ges., 14, p, 76 ; Bot. Zentr., 67, p. 78. 
1# Froc. Roy. Soc., 63, p. 389; 66, p. 177; 72, p. 166. 
11 B. Bot Ges., 24, p. 384. 
