FOXGLOVE . 53 



H. muticus, Linne, Egyptian henbane (Egypt, India) ; leaves 

 entire or toothed, petiolate ; calyx striated, pubescent ; corolla 

 yellow or nearly white ; pyxis cylindrical not urn-shaped. The 

 commercial drug is imported in large quantity from Egypt, often with 

 a considerable proportion of stout, yellowish stalk; used as source 

 of hyoscyamine (0'2 to 1*0 per cent.). 



FOXGLOVE LEAVES 



(Folia Digitalis) 



Source, &C. The purple foxglove, Digitalis purpurea, Linne (N.O. 

 Scrophularinece), is a handsome biennial herb, widely distributed 

 throughout Europe and common in England, where it occurs wild 

 and is also cultivated as a garden plant, as well as for medicinal use. 

 Much of the commercial drug was formerly imported from Germany, 

 but latterly (1915-1918) large quantities have been collected and 

 dried in this country. It appears to have been long used as a domestic 

 medicine ; it was introduced into the London Pharmacopoeia as long 

 ago as 1650, although it did not come into frequent use until about 

 a century later. | ' 



The foxglove produces, like henbane, in the first year a rosette of 

 leaves, but no aerial stem ; in the second year a tall, erect, usually 

 simple stem that may attain a height of 2 metres or more, and bear 

 numerous flowers. The latter are well characterised by their crimson 

 bell-shaped corolla, with darker spots on the inner part of the mouth ; 

 the ovary is conical and contains two cells with numerous ovules ; 

 the stamens are didynamous. 



The plant flowers during the summer months, and the leaves for 

 official use are directed to be gathered from plants commencing to 

 flower, when the presence of the flowers precludes any possibility 

 of the leaves of other plants being collected by mistake. They should 

 be completely dried immediately after collection and preserved quite 

 dry in air-tight containers, when they will retain their activity un- 

 impaired ; air-dry leaves are said to deteriorate rapidly but on this 

 point the evidence is conflicting. 



Description. Foxglove leaves vary usually from 10 to 30 cm. in 

 length, but may attain as much as 15 cm. in breadth ; in shape they 

 vary from broadly ovate to lanceolate, those on the upper part of 

 the stem being the narrower. Towards the base of the leaf the lamina 

 is contracted and passes into a winged petiole of varying length, down 

 which the lower lateral veins are usually decurrent, the petioles of 

 the lower leaves being longer than those of the upper. The upper 

 surface is dull green in colour and bears numerous short hairs, the 

 under surface paler and more or less densely pubescent, the hairs 



