3. Corallorhiza odontorhiza (Willdenow) Poiret, Dict. Sci. Nat. ed. 2. 10: 375. 1818.
Fall coral-root, small-flowered coral-root, corallorhize d’automne
Cymbidium odontorhizon Willdenow, Sp. Pl. 4(1): 110. 1805; Corallorhiza micrantha Chapman; C. pringlei Greenman
Stems yellow, greenish, or purplish brown, base strongly thickened, bulbous. Inflorescences: racemes lax, 11–46 × 1–2.5 cm. Flowers 5–26, inconspicuous; perianth open or closed; sepals and petals reddish purple to brown, often suffused with green, broadly lanceolate, 1–2-veined; lateral sepals strongly curved upward and directed forward, 3–4.5 mm; petals 2.5–3.8 mm, connivent with dorsal sepal to form hood over column, or sepals and petals connivent to produce closed flower; lip white, often spotted with purple, ovate to orbiculate-quadrangular, unlobed, 2.7–4.6 ×1.8–3.7 mm, thin, with 2 distinct basal lamellae, margins entire to erose-fringed; column white basally, often purple apically, 1.9–2.5 mm, straight or curved toward lip, with 2 distinct auricles in open-flowered plants; ovary 2.5–5 mm; mentum inconspicuous. Capsules broadly ellipsoid, 5.5–8 × 3.5–5 mm.
Varieties 2 (2 in the flora): North America, Mexico, Central America.