ASPIDIUM 



33 



from 19 to 31 per cent in the drug, and may be converted into filicic 

 acid by dissolving in alkalies and precipitating with acids. The 

 drug also contains from 0.025 to 0.045 per cent of a light yellow volatile 

 oil with an intense odor of the drug and an aromatic, burning taste. 

 It consists of free butyric and allied acids and hexyl and octyl esters 

 of the fatty acid series, ranging from butyric acid to pelargonic. 

 From 6 to 7 per cent of a green fixed oil is present, which consists of 

 the glycerides of oleic, palmitic, cerotinic and filosymlic acids, the 

 latter being volatile. Also filmaron (active); a small amount of a 

 bitter principle; about 10 per cent of filixtannic acid; a soft black 

 resin and a hard red resin; about 11 per cent of an uncrystallizable 

 sugar; starch, and 2 to 3 per cent of ash. 



FIG. 14. Aspidium: P, parenchyma containing starch grains; S, starch grains; 

 T, tracheae; H, hypodermal cells with thickened walls and simple pores; 

 C, yellow, thick-walled cells of chaff. 



Allied Plants. The rhizome of Aspidium spinulosum appears to 

 possess properties similar to the official drug; it somewhat resembles 

 that of A. Filix mas, but the chaffy scales possess margina.1 glandular 

 hairs and the number of fibrovascular bundles in the rhizome is 

 usually but 6 or 7. 



The, rootstock of Pteris aquilina (Pteridium aquiiinum) contains a 

 cyanogenetic anygdalin-like glucoside. (Bot. Abstracts, 1919, 1, 

 p. 220.) 



