Maran'ta arundina'cea, Arrow-root. -- The fecula of the rhizome, U.S.P. 1820-1870' W. Indies, Bermudas, Brazil. Plant slender, 1-2 M. (3-6 degrees) high, leaves 7.5-12.5 Cm. (3-5' ) long, lanceolate, flowers white, rhizome perennial, tuberous, fleshy, scaly, 15-30 Cm. (6-12') long. Arrow-root in powder or lumps 4 Mm (1/6') thick, white, opaque; under microscope consists of oval granules of fine-lined layers, nucleus at broad end. The rhizome when 1-2 years old is dug, washed, deprived of scales, ground under water, kneaded, strained, and the fecula allowed to subside; fresh rhizome yields starch 13-20 p.c.; root contains starch 27 p.c., fat .2 p.c. Used as demulcent, nutritive food for infants, convalescents, bowel or urinary troubles; in 5 p.c. solution with water or milk by boiling and flavoring with vanilla, lemon juice, etc.; also used in puddings. The jelly is more tenacious than that of all other starches, except Canna.
Can'na ed'ulis, Canna (Tous-les-mois). -- The fecula of rhizome, U.S.P. 1860-1870; Peru, Brazil. Perennial herb 2.5 M. (8 degrees) high; stem green; leaves parallel-veined, bluish-green; flowers few, in pairs, red; yellow, purple, bract; fruit round capsule, 12 Mm. (1/2') thick; rhizome creeping, fleshy, thick joints. Canna starch white powder, satiny; under microscope granules largest of all, potato coming next, 1/12-1/8 Mm. (1/300-1/200') long, flat, ovate, hilum at narrow end, encircled by many unequally distant rings. Grind rhizome under water, knead, strain, allow to subside. Used as demulcent, nutritive food for urinary and bowel affections, infants, invalids in convalescence.