Thu'ja occidental'is, Thuja, Arbor Vitae, N.F. -- The dried, leafy young twigs with not more than 2 p.c. of stems over 4 Mm. (1/6') thick or other foreign organic matter--only the recently dried drug should be used; Canada, United States. Handsome evergreen tree, resembling Chamaecyp'aris sphaeroi'dea (Cupres'sus thyoi'des) 6-15 M. (20-50 degrees) high, trunk crooked, bark pale, shreddy, wood light, soft, durable. Twigs fan-shaped, flattened, leaves appressed in 4 rows, edges boat-shaped, glands on the back; odor strongly balsamic, aromatic, pungent; taste camphoraceous, terebinthinate, bitter. Powder, greenish-brown --chlorenchyma, stomata, guard cells, long fibers, oblique pores; solvent: alcohol; contains volatile oil 1 p.c., resin tannin, pinipicrin, thujin, thujigenin, ash 7 p.c. Stimulant, diuretic irritant, emmenagogue (resembling savin); fevers, bronchial catarrh, rheumatism, dropsy, worms, ulcers, warts. Dose, gr 15--60 (1-4 Gm.); 1. Fluidextractum Thujae (alcohol).