338 ERICACEAE 



411. UVA URSI. UVA URSI 

 BEARBERRY 



The dried leaves of Arctostaph'ylos u'va ur'si (Linne) Sprengel, with not more than 

 5 per cent, of stems or other foreign matter. 



BOTANICAL CHARACTERISTICS. Shrubs with trailing stems. Leaves alternate, 

 coriaceous, evergreen, obovate or spatulate, entire. Flowers in terminal 

 racemes, nearly white; corolla urn-shaped. Fruit a red drupe. 



SOURCE. In dry, sandy, or rocky soil from Hudson's Bay to New Jersey, 

 in some parts of which it grows in abundance. 



RELATED SPECIES. Arctostaphylos glauca, indigenous to California (412). 



DESCRIPTION OF DRUG. Short-stalked, rather thick, coriaceous, obovate 

 leaves, about 20 mm. (% in.) in length, rounded at the apex and 

 narrowed at the base; margin entire; surface smooth, glossy, grayish- 

 green above, lighter colored and reticulated below; taste astringent, 

 bitter; odor slight. (The powder has a hay-like odor.) 



They are sometimes adulterated with the leaves of Vaccinium vitis 

 ideas. (European uva ursi), distinguished from the genuine by their 

 rounder shape, their revolute margin, which is sometimes toothed, 

 and the dotted appearance of their under surface. Chimaphila leaves, 

 which are occasionally mixed with uva ursi, may be readily distin- 

 guished by their greater length, their cuneiform-lanceolate shape, and 

 their serrate edges. Leiophyllum buxifolium (sand myrtle) and 

 Epigcea repens (trailing arbutus, 41 5) are also used as adulterants. 



Powder. Characteristic elements: See Part iv, Chap. I, B. 



CONSTITUENTS. Tannic and gallic acids, and the three principles, 

 arbutin, Ci 2 Hi 6 O7, ericolin, C 3 4H 56 O2i, and ursone, doH^O, which 

 are common to the plants of the natural order Ericaceae. Arbutin 

 is a bitter glucoside, occurring in colorless crystals; it is resolved by 

 hydrolysis into glucose and hydroquinone or arctuvin, C 6 H 6 02. 

 Ericolin is a yellow, crystalline, bitter glucoside. Ursone is in 

 tasteless needles. 



Preparation of Arbutin. Precipitate decoction with lead acetate; filter; add 

 HjS; evaporate; evaporate slowly, when needles crystallize out. Dilute Fe 2 Cl 

 gives blue color. Dose: 5 to 15 gr. (0.3 to i Gm.). 



Preparation of Ursone. Obtained by exhausting drug with ether. The 

 alcoholic solution of the ethereal residue yields the crystals on slow evaporation. 

 Occurs in tasteless needles; sparingly soluble in alcohol and ether. Insoluble in 

 water. 



ACTION AND USES. Astringent, tonic, and diuretic; valuable in ulcera- 

 tions of the kidneys, bladder, or urinary passages. It has been 



