330 SUBTERRANEAN ORGANS 



and Northern Asia. It is common in England in moist situations, 

 attaining a height of 1 to 1-5 metres, and producing terminal corymbs 

 of small white or pinkish flowers, each with a gamopetalous corolla 

 and three stamens. It is cultivated in England (Derbyshire), and 

 also in Holland and Germany, our supplies being derived partly from 

 English and partly from foreign sources, but chiefly from cultivated 

 plants. The drug, or at least a species of valerian, was well known to 

 the Greeks and Romans ; whilst the common valerian, or ' all-heal ' 

 as it is sometimes called, was a domestic medicine of the Anglo-Saxons. 

 In the Middle Ages the root was used not only as a medicine but also 

 as a spice, and, curiously enough, even as a perfume. 



The plant produces a short upright rhizome from which slender 

 horizontal branches are emitted ; the buds that terminate these 

 branches develop into aerial shoots, which in their turn form erect 



FIG. 170. Valerian rhizome. A, transverse, B, longitudinal section 

 through the rhizome : a, bark ; 6, wood ; c, pith ; rd, roots. Natural 

 size. (Berg.) 



rhizomes, and continue the life of the plant, the mother-rhizome 

 perishing after flowering and fruiting. The drug is collected in the 

 autumn, the lateral shoots are cut off for the propagation of the plant, 

 and the rhizomes usually, especially if of large size, sliced longitudinally 

 and dried. 



In Derbyshire the wild plants are collected and planted out ; the 

 stems of the larger which would otherwise produce flowers are topped 

 to prevent this from happening. In September or October all the 

 tops above ground are cut off with a scythe, the rhizomes dug up, 

 washed and dried, the larger being generally sliced. 



Description. The commercial drug consists of short erect conical 

 rhizomes not more than 12 mm. thick and 25 mm. long, of a dull 

 yellowish brown colour, usually halved, or quartered if large, but 

 entire if small, and sometimes crowned with the remains of the stem 

 and leaves. Internally the rhizome is firm and horny and of a whitish 

 or yellowish colour ; sometimes it becomes hollow, portions of the 

 tissue remaining as transverse septa,. 



From the rhizome numerous brittle roots of the same colour and 



