172 



RANUNCULACE^ 



aconite root. It yields japaconitine, stated to be identical with 

 aconitine. 



DESCRIPTION OF DRUG. Almost napiform, abruptly tapering, from 40 

 to 100 mm. long, about the thickness of a finger at the top, which 

 is tuberculated; externally dark-brown, wrinkled longitudinally at 

 lower portion, stem scars visible, rootlets usually detached; fracture 

 short, horny or starchy, exhibiting sometimes a spongy or resinous, 

 white, grayish, or brownish tissue; taste at first sweetish, then acrid 

 and tingling, followed by numbness. This peculiar tingling sensa- 



PlG. 77. Aconite tuber Cross-section. (14 diam.) A, Cork. B, Parenchyma of cortex. 

 C, Vascular bundle. D, Medulla. (Photomicrograph.) 



tion of the tongue is one of the most prominent characteristics upon 

 which the toxicologist depends for the recognition of this drug and 

 its preparations. At the upper portion of the root there often projects 

 a lateral branch connecting a second tuber, which is an offspring of 

 the other. A cross-section of the tuber shows a thick bark and a 

 pith often in the form of a star, the two being separated by a nucleus 

 sheath; the cambium, following the outline of the pith, is also 5- to 

 7-angled, and at the terminal and basal extremities of each ray are 

 found small groups of vascular bundles; these, however, are inclined 

 to follow the whole cambium line. 

 Powder. Microscopical elements of: See Part iv, Chap. I, B. 



ADULTERANTS. With allied aconite roots, defective roots, and horse- 

 radish. The root of European masterwort resembles aconite root, 

 but it is aromatic and pungent. 



CONSTITUENTS. The principal constituent is aconitine, CsJ^NOn 

 (0.5 per cent.), forming about one- third the total alkaloid of the 



