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Materia Munich.—Digitalis folia. »art ii.

gant terminal spike. At the base of each footstalk is a sessilepointed floral leaf. The uppermost segment of the calyx isnarrower than the other four; the corolla is monopetalous, ofan oblong hell-shape, and about the size of the little finger ofan ordinary glove; bellying on the lower side, with a shorttubular hase. The upper lip is lightly cloven, and more re-flected than the under, which is larger. The corolla is guardedby long hairs at the mouth: its general colour is a brightpinkish purple, with the tube white, and the bellying partsprinkled on the inside with dark purple spots on a whiteground, which give to the outside a speckled appearance. Thefilaments are white, curved, bearing large oval yellow anthers;the germen is pointed, supporting a simple style with the apexcloven. The seed-vessel, which is a pyramidal capsule with adouble partition produced by the inflected margins of thevalves % contains many small ferrugineous, punctated seeds.

The leaves are the parts of the plant medicinally used.They should be gathered when the plant is in flower, and thoseonly which are fresh selected. " The leaf-stalks and midribshould be rejected, and the remaining part be dried eitherin the sun-shine, or on a tin-pan or pewter dish before thefire, or the plant be hung up, each leaf separate, in a warmkitchen.'* Practitioners ought annually to obtain a supply ofthe recent leaves, in the month of July, and dry them them-selves; as in the herb-shops they are often so ill dried as toappear black, in which state tbey are useless. Tbe powdershould be kept in closely stopped opaque phials.

Qualities. —-Recent foxglove leaves are inodorous; but intbe dried state they havte a slight narcotic odour, and a bitternauseous taste. Both water and alcohol extract their virtues.The watery infusion has a pale olive green colour, with theunpleasant odour and taste of the plant. It does not precipitatesolutions of galls, tartarized antimony, nor sulphate of iron,which only deepens its colour, but it produces a yellowish pre-cipitate with muriate of mercury, and a blackish violet very copi-ous one with nitrate of silver. The dry powder, which shouldhave a beautiful green colour, moistened and triturated withlime or calcined magnesia, and a glass rod dipped in muriaticacid held over it, exhibits copious white fumes, proving thepresence of ammonia. The presence of ammonia is also appa-rent in the tincture; which is rendered milky by water. 1 Tengrains of the powder macerated in fjss of sulphuric ether lost

1 Gartner de Fructibus, &c. i. 247. t. 53. f. 6.

B Destouchcs, a French chemist, who analysed Foxglove, obtained also muchcarbonate of ammonia by distilling the aqueous extract. He obtained besides sul-phate of potash and of lime, phosphate of lime, carbonates of lime, and of potash,and acetate of ammonia.