68o BOTANY AND PHARMACOGNOSY. 



it forms little or no foam when mixed with an equal volume of 

 alcohol and shaken with ammonia water, indicating the absence 

 of turpentine and fixed oils. 



Constituents. Storax consists of about 50 per cent, of two 

 resin alcohols, a-storesin and /3-storesin, which are partly free, 

 partly in combination with cinnamic acid and partly with sodium. 

 a-STORESiN (a-storesinol) is an amorphous substance that is very 

 sparingly soluble in water and forms a crystalline compound with 

 potassium. /J-storesin (|8-storesinol ) occurs in white flakes 

 which are somewhat soluble in water but do not form a crystal- 

 line compound with potassium. Storax also contains from 10 to 

 20 per cent, of an ester consisting of cinnamic acid and storesin ; 

 from 5 to TO per cent, of cinnamyl or styryl cinnamate (styra- 

 cin) which occurs in colorless, odorless and tasteless needles 

 and which on hydrolysis yields cinnamic alcohol (styrone) and a 

 salt of cinnamic acid ; about 10 per cent, of an odorless, viscid 

 substance, phenyl propyl cinnamate; from 2 to 3 per cent, 

 of phenyl ethylene (styrol or styrene), which occurs as a 

 colorless liquid possessing the odor and pungent taste of storax; 

 from 0.5 to I per cent, of a volatile oil which is Isevo-rotatory 

 and consists of a hydrocarbon, styrene, about 0.4 per cent, of an 

 oxygenated compound (styrocamphene), and cinnamates of ethyl, 

 benzyl, phenyl-propyl and cinnamic alcohols ; from 2 to 5 per 

 cent, of free cinnamic acid ; a small quantity of iso-cinnamic acid 

 which occurs in colorless crystals ; a crystallizable susbtance, 

 styrogenin ; about 0.15 per cent, of vanillin; a trace of benzoic 

 acid ; ethyl vanillin ; resin, and caoiitchouc. Storax sometimes 

 yields more than 20 per cent, of free cinnamic acid and is the 

 best available source of this substance. 



Allied Plants. Liquidamhar Styraciflua, a tree indigenous 

 to the Eastern and Southern United States and Mexico, yields the 

 American storax, which occurs as a yellowish-brown, semi-liquid 

 mass somewhat resembling Levant storax. It probably contains 

 related storcsins (storesinols), which appear to form similar com- 

 binations with cinnamic acid. On distillation of the fresh balsam 

 about 7 per cent, of a volatile oil is obtained, which is dextro- 

 rotatory and contains styrol and a body with the odor of oil of 

 turpentine, the cinnamyl-ethyl-ester and cinnamyl-benzyl-ester 



