LEAVES. 305 



India, in which country it is probably indigenous. It has 

 recently come into cultivation in the West Indies and 

 other tropical lands. It is an annual plant, with stems 

 two or three feet high and leaves two or three inches long. 

 The flowers are yellowish, and have an aromatic odor. The 

 rhizome, powdered or otherwise, constitutes the Ginger 

 of commerce. It contains about one per cent, of vola- 

 tile-oil, which is thin and reddish-yellow. The rhizome 

 contains also starch, resin, etc. It is used in obtaining 

 the oil, which is employed in cooking, for flavoring liquors, 

 etc. Ginger is a mild stimulant and carminative, and has 

 been used as a spice from early times. 



295. The Sweet Flag (^Acorus Calamus) has a fleshy 

 aromatic rhizome called Calamus. The plant grows in 

 Europe, Asia, and North America, in marshy or wet 

 places. It has a spadix of greenish flowers ; the leaves are 

 long, radical, and sword-shape. The rhizome is collected 

 in the fall, when it contains the largest amount of reserve 

 material. It is -then washed and dried, and used in the 

 manufacture of oil of calamus, yielding about one per 

 cent., which is found mainly in the cortex ; or if to be 

 employed in medicine the cortex is removed. The odor as 

 well as taste of the rhizome is aromatic. It is Used by 

 confectioners, also in preparing aromatic vinegar and some 

 other articles, 



LEAVES. 



296. The Dyer's-\weedor\Veld, Reseda luteola (family 

 Resedaceee), is an erect, herbaceous, European plant, about 

 two feet high; the leaves are small, alternate, lanceolate, 

 with a tooth on each side at the base; the flowers are 

 greenish-yellow in a long spike. This plant has been 



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