280 POLYGALE^E 



evaporated at a low temperature. Boiling water extracts apothem, the pres- 

 ence of which is a detriment to the astringent principle. 



ACTION and USES. A powerful astringent, with some tonic properties. Dose: 

 5 to 30 gr. (0.3 to 2 Gm.). 



302. SENEGA. SENEGA 



SENEKA. SENEGA SNAKEROOT 

 The dried root of Polyg'ala sen'ega Linne". 



BOTANICAL CHARACTERISTICS. Stems several, from a thick and hard, knotty 

 root-stock; leaves lanceolate, with rough margins; calyx with 3 sepals, small, 

 greenish, and 2 larger (called wings), colored; flowers white, in a solitary, 

 close spike. 



SOURCE. Almost all parts of the United States east of the Rocky Moun- 

 tains. It is collected for market in Kentucky and in the states west 

 and southwest of it, and in Wisconsin, and in immense quantities 

 in northern Minnesota. This latter variety is known as northern 

 senega. It is, as a rule, a larger root than the southern; the anatom- 

 ical and structural differences between the two roots are probably 

 very slight. Poly gala alba, Nutt., inhabits Western Texas and West- 

 ern Kansas, but this variety of senega is not systematically collected 

 for the market as are the roots of Minnesota and Kentucky. 



DESCRIPTION OF DRUG. A contorted root, about 100 mm. (4 in.) long, 

 with a knotty crown bearing numerous remnants of scaly leaves. 

 The main root is from 5 to 10 mm. (% to % in.) thick, fleshy, but void 

 of starch. It varies in color from a light yellow to a dark brown 

 externally; much-branched, the branches spreading, tortuous, longi- 

 tudinally wrinkled, annulate near upper end; bark thickish, inclosing 

 a porous, yellowish wood, but easily separable from it; it consists of 

 three layers, the inner one excessively developed on one side, forming 

 a prominent cord or keel on drying, fracture short when dry. Odor 

 faint, sometimes wintergreen-like; taste sweetish, afterward acrid 

 and nauseating. The liquid preparations of it have a characteristic 

 nauseous odor. 



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



CONSTITUENTS. The acrid principles to which its medicinal action is 

 entirely due, are polygalic acid, Ci 9 H 3 oOio, and senegin, CnHzeOio 

 two homologues. The distinction between polygalic acid and senegin 

 is mainly one of solubility in alcohol (the former more soluble). Lead 

 acetate precipitates polygalic acid, but does not precipitate senegin. 

 The root also contains a fixed oil, and a small quantity of volatile oil,, 



