9

9

Fig. 163. RHUS GLABRA FRUIT.

a, b. Deep red many celled trichomes.

c. Colorless trichomes.

d. Outer layer of seed coat, lateral view.

e. Thick-walled porous cells of testa.

f. Colorless crystal bearing layer of testa. 9. Endosperm cells.

h. Parenchyma of pericarp.

i. Epidermal cells of pericarp.

168. ROSA GALLICA. Red Rose. U. S.

Fl. ex. 30.

Essigrose, Sammtrose, Zuckerrose, G. Rose rouge, Rose de Provins, Fr.

The petals of Rosa gallica L., Rosacea.

Light purplish red.

Fragrant; rose odor.

Very astringent, acidulous, bitterish.

Upper epidermal cells vertically elongated, conical, with granules of purple coloring matter. In vertical view these cells appear thickwalled polygonal, indistinct in coarse powder, cuticle smooth. Lower epidermal cells larger, not elongated, vertical walls somewhat wavy, irregular; cuticle finely wavy, short linear striate; no coloring matter. Parenchyma cells rounded, empty. Spiral ducts.

Ash 3.5 per cent.

Adulterated with the petals of various red roses or petals of the white or pink roses colored with red dye as fuchsin.

169. Fig. (164.) RUBUS. Blackberry.

Fl. ex. 60.

Brombeerrinde, G. Ecorce de rouce noir, Fr.

The root bark with some of the wood of Rubus villosus Aiton, R. canadensis L., and R. trivialis Michaux, Rosaceæ.

Very light brown.

Odorless.

Very astringent, bitter.

Outer layer of brown cork. Inner bark parenchyma of thin-walled, closely united cells bearing simple spherical starch granules. Bast fibers with walls of medium thickness, porous, containing some starch; outer walls of bast appear shreddy. A few short sclerenchymatous tracheids accompany bast fibers. Numerous tracheids and porous ducts from wood remnants of roots.

Compare the histology of the three official roots. May be adulterated with roots and rhizomes of other plants.

a. Bast fibers, some starch and a few sclerenchymatous fibers.

b. Parenchyma with starch.

c. Cork.

d. Ducts and tracheids.

170. (Fig. 165.) RUMEX. Rumex.

Fl. ex. 30.

Yellow Dock, E. Grindwurzel, Mengelwurzel, G. Racine patience frisée, Fr.

The roots of Rumex crispus L., and other species, Polygonaceæ. Brown.

Somewhat aromatic; nearly odorless.

Very bitter and astringent.

Thin-walled brown cork tissue. Parenchyma cells large; thinwalled, loosely united, filled with granular matter and simple, elliptical, oval and egg shaped starch granules. Rather large aggregate crystals of calcium oxalate abundant. Yellow brown sclerenchyma cells, somewhat variable in thickness of walls and in form. Bast, tracheids and reticulate ducts.

Related species of dock (Rumex) are subtituted for the above.