296 



SUBTERRANEAN ORGANS 



size. Towards the autumn the parent plant dies down, and the 

 daughter roots, which have then attained their maximum development, 

 are plump and full of starch. If allowed to remain in the soil the 

 buds that crown the daughter roots begin to grow in the late winter 

 or very early spring, and this growth is effected at the expense of the 

 starch in the root, which for that purpose is converted into sugar. 

 The root therefore becomes gradually exhausted of its reserve material, 

 and it is generally assumed that the proportion of alkaloid it contains 

 simultaneously diminishes, although this assumption has not been 

 confirmed by analysis, such assays as have been made having shown 

 but little difference. In some continental countries the wild plant 



is considered to be more active than 

 the cultivated, and as experiments 

 have shown that A. Napellus is more 

 toxic than A. variegatum, Linne, and 

 its varieties, the root is directed to 

 be gathered from wild plants when 

 in flower, at which time they can be 

 most easily distinguished. Hence the 

 aconite root that is imported in 

 large quantities from Germany con- 

 sists chiefly of the partially exhausted 

 summer (parent) roots of the wild 

 flowering plants. 



After collection the roots are 

 washed, freed from the rootlets and 

 dried, sometimes entire, sometimes 

 longitudinally sliced. 



FIG. 148. Aconite root. Transverse 

 section of daughter root, a, 

 bark ; b, cambium ; c, wood. 

 Magnified 3 diam. (Berg.) 



Description. Aconite root of com- 

 merce varies usually from 5 to 10 

 cm. in length, although the entire 



root is often considerably long e r. At the upper extremity, w T here 

 it is crowned with an undeveloped bud enclosed by scaly leaves 

 (daughter root), or by the remains of the aerial stem (parent 

 root), it is about 1 or 2 cm. in diameter, tapering rapidly down- 

 wards. It is dark brown in colour, and marked with the scars of 

 rootlets. The surface is usually longitudinally wrinkled, especially 

 if it has been dried entire. The root breaks with a short fracture, 

 and should be whitish and starchy internally. The smoothed 

 transverse section exhibits a thick bark, separated from the inner 

 portion by a well-marked, darker, stellate line (cambium), with a 

 group of vessels distinctly visible at each of the projecting angles, 

 usually five to seven in number. Commercial aconite root is, however, 

 often yellowish or brownish internally, and does not readily show the 

 stellate cambium ; this is probably due to its having been collected 



