186 



SCIENTIFIC AND APPLIED PHARMACOGNOSY 



used in those countries. It very closely resembles Asarum, is of a 

 grayish- or reddish-brown color, with an aromatic and pungent 

 taste and the powder is sternutatory. It contains 1 per cent of a 

 volatile oil which consists in part of a camphor known as asarin or 

 asaron; 1 per cent of tannic acid colored green with ferric salts; 

 2 per cent of starch and 0.15 per cent of resin. 



Serpentaria. The rhizome and roots of several species of 

 Aristolochia (Fam. Aristolochiacese), perennial herbs indigenous to 

 the southern United States. There are two commercial varieties: 



FIG. 78. Serpentaria (Virginia snakeroot) showing oblique rhizomes with numer- 

 ous long, slender roots. 



(1) Virginia Snakeroot, yielded by Aristolochia Serpentaria, found 

 growing east of the Mississippi, and (2) Texas or Red River Snake- 

 root, yielded by Aristolochia reticulata, growing west of the Mis- 

 sissippi. The rhizome and roots are collected in autumn and dried 

 (Fig. 78). 



Virginia Snakeroot. Rhizome oblique, sub-cylindrical, with 

 numerous slender roots and frequently with leaves or fruiting stems, 

 10 to 25 mm. in length, a^d 1 to 2 mm. in diameter; externally dark 

 brown, slightly annulate from scars of bud-scales, upper portion 



