POWDERED DRUGS AND FOODS. 729 



hairs resembling those of digitaHs. The non-glandular hairs of 

 Inula Conysa (Fam. Compositse) are 3- to 4-celled, with thick 

 walls, the basal cell being broad and truncate. 



34. HEDEOMA. — Dark green; non-glandular hairs slightly 

 curved, 2- to 3-celled, thick-walled, with numerous slight centrif- 

 ugal projections ; glandular hairs with i -celled stalk and 8-celled 

 glandular head; pollen grains somewhat spherical, about 35 /a in 

 diameter, nearly smooth ; tracheae spiral or with simple and bor- 

 dered pores ; sclerenchymatous fibers long, thin-walled, lignified, 

 with numerous simple pores ; epidermal cells with sphere-crystals 

 or irregular masses of a carbohydrate. 



35. MARRUBIUM. — Dark green; non-glandular hairs much 

 twisted, I- to 7-celled, thin-walled, smooth, frequently arranged 

 in groups of about six or eight, and spreading from the base ; 

 glandular hairs with i -celled stalk and 8-celled glandular head; 

 pollen grains spherical, about 25 /u, in diameter, and with numerous 

 centrifugal projections ; tracheae spiral, annular, or reticulate, 

 slightly lignified ; sclerenchymatous fibers thin- walled. non-Iigni- 

 fied, with few simple pores. 



36. MENTHA PIPERITA.— Dark green; non-glandular 

 hairs i- to 8-celled, thin-walled, with numerous slight projec- 

 tions; glandular hairs two kinds, i- or 3-celled stalk and i- or 

 8-celled glandular head ; pollen grains somewhat spherical, smooth, 

 about 35 IX in diameter ; tracheae spiral, or with simple and bor- 

 dered pores, and slightly lignified ; sclerenchymatous fibers thin- 

 walled, non-lignified, with numerous oblique pores. Contamina- 

 tion with M. spicata is said to be common. 



37. SCUTELLARIA. — Dark green ; non-glandular hairs, i- 

 to 3-celled, 100 to 200 fjL long, the walls with numerous slight 

 centrifugal projections, the basal cell being large, broadly cylin- 

 drical, and the apical cell narrow and with a sharp, frequently 

 recurved apex; glandular hairs with a i- to 2-celled stalk and 

 large, glandulai head, composed of 6 or 8 cells placed side by 

 side, indistinct ; pollen grains nearly spherical or ellipsoidal, 

 smooth and 15 to 25 /.i in diameter; fragments of corolla colored 

 light pink with chloral solution ; narrow tracheae with scalariform 

 and reticulate thickenings, or bordered pores; sclerenchymatous 

 fibers narrow, with walls 4 or 5 /a thick and with simple pores ; 



