193 



and an odour of burnt sugar; dissolves little in cold, readily in 

 boiling water, the light-yellow solutions becoming colourless with 

 acids; little soluble in cold, more so in hot alcohol, not in ether, 

 readily in alkalies with gold-yellow colour; the ammoniacal solu- 

 tion becomes brown by keej^ing, but not the solutions of the fixed 

 alkalies; breaks up with diluted acids into sugar and quercetin. 



R0CCellicAcid=C34 H30 Oe + 2 HO. In Roccella fuciformis 

 and in Lecanora tartarea. Treat with water and ammonia, preci- 

 pitate the filtrate with chloride of calcium, decompose the deposit 

 with hydrochloiüc acid and purify the crystals that have form^id 

 by dissolving in ether. — Forms delicate, white, silvery, quadrangu- 

 lar, tabular crystals, obtained in short needles from alcohol, 

 inodorous and tasteless, of acid reaction in the alcoholic solution ; 

 fuses at 130° without loss of weight, evaporates partly below 200°, 

 and is partly converted into the anhydrous acid and decomposed 

 by a higher temperature ; is quite insoluble in water, dissolves in 

 1*8 parts alcohol of 0'819, readily in ether; foi'ms with alkalies half- 

 acid soluble, with the other bases mostly insoluble salts. 



R0CCellillili:=C36 Hie O14. In Roccella tinctoria. Treat with 

 water containing lime, filter, precipitate the filtrate with hydro- 

 chloric acid and boil the deposit, consisting of Roccellinin and 

 lecanoric acid (named formerly /Sorsellic acid), repeatedly with 

 water, leaving the R. undissolved, which has to be recrystalliseil 

 in alcohol. — Fine, hair-shaped crystals of silky gloss, insoluble in 

 water, slightly soluble in cold alcohol and in ether, a little more 

 when hot, readily in alkalies and in alkaline eartlis ; assumes a 

 permanent green-yellow colour with solutions of chloride of lime. 



Rottlerill (Kamalin) = C-22 Hio Oe- In the kamala, the 

 stellated hairs and glandules that cover the fruit of ]\Ial lotus 

 Philipinensis. It crystallises from the ethereous tincture in yellow 

 needles of a silky gloss, fuses by heat and becomes decomposed 

 in higher temperatures; is insoluble in water; dissolves in alkalies 

 with deep-red colour, little in cold, more in boiling alcohol, and 

 readily in ether. 



Ruberythric Aci(l=C72 H40 O40 or C56 H3: O31. In the root 



of Rubia tinctoi'um, according to Roclileder; Sclunick believes the 

 above acid to be a product of decomposition of rubian, and perhaj s 

 identical with a substance named by him rvibianic acid. Precipitate 

 with acetate of lead the aqiieous decoction of madder, remove the 

 de]")Osit (which may be used for the preparation of alizarin and 

 purpurin), and precipitate the filtrate with subacetate of lead, but 

 not in excess, producing a dark flesh-coloi;red find almost brick-red 

 deposit, Avhich contains Euberythric, rubichloric, a little citric and 

 phosphoric acids. Decompose the deposit under water with sul- 

 phiu-et of hydrogen; separate the liquid, containing mostly rubi- 







