ALKANNA 369 



vehicles to disguise the taste of disagreeable medicines like quinine. 

 Dose: 15 to 30 gr. (i to 2 Gm.). 

 OFFICIAL PREPARATION. 



Fluidextractum Eriodictyi, Dose: 15 to 30 TOR. (i to 2 mils). 



BORRAGINACE^:. Borage Family 



465. ALKANNA. ALKANET. The root of Alkan'na tincto'ria Tausch. Hab- 

 itat: Grecian Archipelago and Southern Europe. Fusiform, about 100 mm. 

 (4 in.) long, from the thickness of a quill to that of the little finger, often 

 crowned with soft, white, hairy root-stocks; the bark is of a dark-purple 

 color, friable, and separates easily in thin, papery layers from the yellowish, 

 twisted ligneous column; the wood is composed of distinct, slender wood- 

 fibers cohering together and cleft by purple, friable, medullary rays; in 

 the commercial samples, however, it is generally more or less decayed, loose, 

 and spongy. Odorless and tasteless. Alkanna is employed exclusively for 

 coloring oils, ointments, and plasters, which is accomplished by suspending 

 it, tied up in a rag, into the melted fat. Its coloring principle has been 

 termed alkannin; it is a red, resin-like substance, soluble in alcohol, ether, and 

 fats, but insoluble in water. 



Preparation of Alkannin. Obtained by evaporation of ethereal tincture, or 

 precipitating a weak alkaline aqueous solution of alkanet by an acid. 



466. SYMPHYTUM. COMFREY. The root of Sym'phytum officina'le Linn<. 

 Habitat: United States and Europe; cultivated. About 150 mm. (6 in.) or 

 more long, and from the thickness of a quill up to an inch in diameter, often 

 split; externally black, wrinkled; internally whitish, and horny when dry; 

 inodorous; taste sweetish, astringent, and very mucilaginous, containing 

 as much mucilage as, or more than, althaea, for which it may often be sub- 

 stituted. It is chiefly used as a demulcent in domestic cough remedies, and 

 has been highly esteemed as a vulnerary. Dose: 2 to 4 dr. (8 to 15 Gm.). 



467. BORAGO OFFICINALIS Linn<. BORAGE. Habitat: Europe. (Leaves.) 

 They contain a large quantity of mucilage, with potassium nitrate and other 

 salts, upon which their virtues depend. Diuretic, refrigerant, demulcent, 

 etc. Dose of fluidextract: i fl. dr. (4 mils). 



468. PULMONARIA OFFICINALIS Linne. LUNGWORT. Habitat: Europe. 

 (Leaves.) Pectoral and demulcent. Dose: 30 to 60 gr. (2 to 4 Gm.). 



VERBENACE^;. Vervain Family 



469. LIPPIA MEXICANA. The leaves of Lip'pia dul'cis Treviranus. Demul- 

 cent and expectorant. Dose: 8 to 15 gr. (0.5 to I Gm.). 



470. VERBENA HASTATA Linn<. AMERICAN BLUE VERVAIN. (Root and 

 Herb.) (Verbena, N.P., is the dried overground portion of the plant, col- 

 lected when flowering.) The hot infusion is used as a sudorific in colds, etc. 

 Also tonic and expectorant. Dose of fl'ext.: 30 to 60 1$ (2 to 4 mils). 



471. VERBENA URTIC^FOLIA Linne'. WHITE VERVAIN. Habitat: Trop- 

 ical America. (Root.) Febrifuge. Credited with the cure of the opium- 

 habit. Dose of fl'ext.: 30 to 40 njj (2 to 2.6 mils). 



472. TONGA. A drug introduced under this name has been found to be a mixture 

 of bark, leaves, and woody fibers, tied into bundles by means of the inner 

 bark of the cocoanut tree. The bark comes from Premna taitensis (nat. ord. 

 Verbenaceae), a shrubby tree having a sweet and slightly astringent inner bark, 

 containing little volatile oil, etc. The fibrous material comes from Rha- 

 phidophora vitiensis (nat. ord. Araceae), a creeper having a stem about the 

 size of a quill, containing potassium chloride, a volatile alkaloid, tongine, etc. 

 From this mixture a fi'ext. is prepared which has proved efficient in neural- 

 gia. Dose of fl'ext.: I fl. dr. (4 mils). 



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