POWDERED DRUGS AND FOODS. 717 



6. STRAMONII FOLIA.— Dark green (Fig. 117); cal- 

 cium oxalate in rosette aggregates 10 to 20 /* in diameter; 

 non-glandular hairs few, 2- to 3-Gelled, with numerous slight 

 centrifugal projections; glandular hairs few, stalk i- to 2-celled, 

 glandular head 2- to 4-celled (Figs. 106, A; 285, C; 287, D). 



b. GLANDULAR HAIRS WANTING. 



7. PILOCARPUS.— Dark green (Fig. 257) ; epidermal cells 

 on surface view 5- to 6-sided, walls straight; calcium oxalate 

 crystals in rosette aggregates, 20 to 30 /j. in diameter, frequently 

 in palisade cells and also in cells in the air spaces of the stomata ; 

 mesophyll cells frequently with reddish-brown tannin masses, 

 turning green with ammonio-ferric sulphate solution; non-gland- 

 ular hairs i -celled, thick- walled, with numerous slight centrifugal 

 projections, 0.4 to 0.6 mm. long in P. Jaborandi and 40 to 60 /* 

 in P. pinnatifolitis and P. microphyllus. In P. microphyllus the 

 stomata are smaller than in the other two species. 



8. TEA. — Large, elongated, irregular and colorless stone 

 cells (idioblasts) ; numerous unicellular, long, thick- walled, non- 

 glandular hairs 10 /x wide ; rosette aggregates of calcium oxalate 

 10 fjL in diameter; characteristic stomata 30 to 60 /^ in diameter, 

 with 3 or 4 accompanying cells. Adulterants are distinguished 

 by possessing chiefly other forms of calcium oxalate crystals and 

 hairs. 



Allied Plants. — Mate or Paraguay tea (p. 322) is distin- 

 guished by the stomata, which are much larger than the epi- 

 dermal cells of the lower surface; the epidermal cells occurring 

 near the veins are in nearly parallel rows and with a striated 

 surface; sclerenchymatous fibers are associated with the tracheae, 

 and calcium oxalate occurs in rosette aggregates. 



Adulterants. — Ash leaves (species of Fraxinus) have 

 rather characteristic " horned " stomata, due to the extra develop- 

 ment of the cutinous layers at the poles of the stomata ; the epider- 

 mal cells are very wavy in outline. Camellia leaves contain idio- 

 blasts (similar to those in tea leaves) and calcium oxalate crystals, 

 but the lower epidermis is thick-walled and with centripetal thick- 

 ening. Cherry leaves (Prunus avium) have numerous small rosette 



