CHRYSOPHANIC ACID, ETC. 93 



CHRYSOPHANIC ACID. 



Cells which contain this acid are colored deep 

 red by potassic hydrate. The hyphae of lichens 

 are also colored red by the reagent, and are dis- 

 solved by it. On the other hand, calcic hydrate 

 or barium water colors them without dissolving 

 them. Ammonium carbonate gives no color with 

 this substance, and hydrochloric acid does not 

 affect it. When gently warmed, chrysophanic 

 acid reduces the ammonium nitrate of silver. 1 



FATTY OILS 



Form strongly refractive spherical masses, soluble 

 in ether, carbon bisulphide, benzole and oil of 

 turpentine. They form soap with potash or sodium 

 lyes. Perosmic acid, if not too dilute, colors them 

 black or brown. 



When very closely united with protoplasm, fats 

 can be separated by concentrated sulphuric acid 

 or an aqueous solution of chloride of calcium, 

 when they collect in drops of varying size, espe- 

 cially at the margin of the preparation. 



VOLATILE, ETHEREAL, OR ESSENTIAL OILS 



Form ropy, motile, refractive masses, often very 

 long in proportion to their diameter. They are 



l Cf. Schwarz: Cohn's Beitr. z. Biol. d. Pfl., 1880, III., p. 249. 



