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SCIENTIFIC AND APPLIED PHARMACOGNOSY 



to 2 mm. in thickness, cambium irregular, 5- to 7-angled, wood 

 yellowish, in small bundles at the angles, pith light brown, about 2 

 to 6 mm. in diameter; odor very slight; taste sweetish, acrid, pun- 

 gent, accompanied by a sensation of numbness and tingling. 



The shrunken, hollow, older tubers, together with the over- 

 ground stem-remnants, should be rejected. 



Inner Structure. See Fig. 93. 



FIG. 93. Transverse section of aconite: K, cork; E, epidermis; ST, stone cells; 

 EN, endodermis; C, cambium; T, tracheae; P, parenchyma. 



Powder. (Fig. 94.) Grayish-brown to dark brown; starch 

 grains numerous, spheroidal, somewhat plano-convex, single or 

 2- to 5-compound, the individual grains from 0.003 to 0.015 mm. 

 in diameter and frequently with a central cleft; tracheae mostly 



