POWDERED DRUGS AND FOODS. 793 



taper gradually towards the base as well as towards the apex. 

 The other tissues of the pericarp are not so conspicuous as in 

 the other cereals (Fig. 120). 



246. NUX VOMICA.— (See No. 252.) 



247. ORRIS ROOT. — Characteristic starch grains 15 to 30 /* 

 in diameter; scalariform tracheae 25 ju. in diameter; no cork; 

 calcium oxalate in raphides or in long pyramids (Figs. 317, A, 

 320). Coarse angular fragments of orris root, which have been 

 colored with yellow, green and red aniline dyes, are sometimes 

 present in a so-named Japanese pot pourri which is used for filling 

 rose jars. 



248. OUILLAJA.— (See No. 210.) 



249. BRYONIA. — Starch grains single or two or more com- 

 pound, from 10 to 20 jtt in diameter; occasional acicular crystals 

 200 ju in length ; tracheae 35 to 60 /x wide, associated with yellowish 

 colored cells ; cork cells yellow ; powder colored purplish and 

 reddish-brown with sulphuric acid. 



249a. CALAMUS.— (See No. 128.) 

 249b. ULMUS.— (See No. 129.) 



j8 Soluble in or Swelling in Cold Water to Form a Sticky Mass. 



250. TRAGACANTHA.— Slowly affected by water; frag- 

 ments of tracheae and parenchyma; starch grains more or less 

 spherical and from 2 to 10 /* in diameter (p. 652). 



B. WITHOUT STARCH. 



a. CALCIUM OXALATE PRESENT. 



251. SCILLA. — Raphides very long, being sometimes i or 2 

 mm. in length, and occurring either in mucilage cells or free in 

 the powder or agglutinated mass ; also isolated fragments of fibro- 

 vascular tissue (Fig. 281, B). 



b. CALCIUM OXALATE WANTING. 



252. NUX VOMICA.— Grayish-white (Figs. 283, B; 318) ; 

 odor slight; taste intensely and persistently bitter; epidermal cells 

 modified to strongly lignified hairs; endosperm cells containing 



