518 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



be distributed mucilage cells or branched spicular cells; the outer 

 walls of the lower epidermal cells may be papillose, or even show cork 

 formation. In the Loganioidese the non-glandular hairs are either 

 unicellular or uniseriate, those in Strychnos having a specific value. 

 In Spigelia there are developed stellate hairs composed of single 

 united cells, which are inserted upon a multicellular stalk. True 

 glandular hairs, having flattened heads, are only found in Buddle- 

 ioideae. 



GELSEMIUM. Yellow Jessamine, Yellow Jasmine. The dried 

 rhizome and roots of Gelsemium sempervirens (Fam. Loganiacese), 

 a smooth, perennial climber of the southern United States and 

 Guatemala. The drug should be collected in autumn. 



Description. Rhizome horizontal, cylindrical, usually cut into 

 pieces 3 to 20 cm. in length, 4 to 30 mm. in diameter; externally light 

 brown, also somewhat purplish-brown, longitudinally wrinkled, 

 transversely fissured; upper surface with few stem-scars; under and 

 side portions with numerous roots and root-scars; fracture tough, 

 wiry; internally light brown or pale yellow, bark about 1 mm. in 

 thickness; wood distinctly radiate, excentral, with four groups of 

 intraxylary phloem, pith disintegrated; odor slight; taste bitter. 



Roots light brown; 3 to 20 cm. in length, 2 to 8 mm. in thick- 

 ness; internally light yellow, bark about 0.5 mm. in thickness; 

 wood distinctly radiate. 



The overground stem is dark or reddish-brown, longitudinally 

 wrinkled and has numerous lenticels and few, somewhat elliptical 

 branch-scars; the bark is about 0.2 mm. in thickness and somewhat 

 greenish. 



INNER STRUCTURE. See Figs. 217 and 218. 



The alkaloids are localized in the epidermal cells and in the 

 parenchyma of the vascular bundles, and may be somewhat easily 

 determined (Fig. 219). They also may be detected by the use 

 of certain reagents. A solution of iodin and potassium iodide 

 gives a reddish-brown precipitate; nitric acid colors the cells a 

 deep yellow and in which needle-shaped crystals of the nitrates 

 may separate; solutions of platinic chloride, gold chloride, or picric 

 acid form yellow precipitates; phosphomolybdic acid gives a yel- 

 lowish-white precipitate; vanadic and sulphuric acids produce a 

 red color which is slowly changed to green. Other alkaloidal reagents 

 also may be employed. 



Powder. Dark yellow; tracheae with simple pores; scleren- 

 chymatous fibers long, narrow, lignified; starch grains spheroidal, 

 from 0.004 to 0.010 mm. in diameter; calcium oxalate in long mono- 



