188 POWDERED VEGETABLE DRUGS 



5. (Fig. 5.) ACONITE ROOT. U. S. 



Fl. ex. 40. Tinct. 60. 



The roots of Aconitum napellus L. Ranunculaceae. 



Dry, slightly starchy or mealy feel. 



Light brown. 



Odor faint, recalling horseradish when moist. 



Taste sweetish, very markedly and persistently acridly pungent; 

 acridity especially marked in the fauces. Benumbing effect. 



Predominating elements are derived from the more or less broken, 

 large, rather thick-walled, essentially isodiametric closely united 

 parenchyma cells filled with compound starch granules. A few 

 slightly brownish,, essentially rectangular only slightly elongated, 

 rather thin-walled, very porous sclerenchyma cells, which generally 

 occur singly, rarely in twos. Some porous ducts and tracheids; 

 spiral ducts rare ; 



Starch granules singly, in twos, fours and in aggregates of from five 

 to seven; hili distinct in the larger granules, centric; single granules 5/* 

 to 15/x; cross bands quite distinct, broad, right angled. There should 

 be no thick- walled sclerenchyma, no true bast, and vascular tissue 

 should be sparingly present. 



Ash about 5 per cent. Impurities should not exceed 5 per cent. 



Deep yellow with potassium hydrate solution. Deep red with 

 concentrated sulphuric acid. 



Among the possible adulterants are horseradish (simple, oval to 

 elliptical starch granules, 5/* to 15/z, with very indistinct hili and 

 lamellations) ; A. Fischeri, (starch granules mostly simple and in 

 twos and the aggregates of five to nine). Single granules somewhat 

 larger than in A. napellus and some of the sclerenchyma cells con- 

 siderably elongated ; Japanese aconite (sclerenchyma cells wanting) . 

 Suspect other species and varieties of aconite, also the use of exhausted 

 powder, crowns and stem parts (fibrous tissue excessive and a few 

 2- to 5-celled trichomes). Suspect roots from other groups of plants. 



