This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Leafy plants, with biennial 2-cleft tubers. Flowers greenish in a long leafy-bracted spike. Sepals free, somewhat arcuate, bent together and forming a hood. Petals narrow. Lip oblong, obtuse, 2-3-toothed at the apex. Spur much shorter than the lip, blunt, sac-like. Column short. Pollinia with long caudicles. Glands small, scarcely wider than the caudicle, surrounded by a thin membrane. [Latin, heaven-tongue.]
A boreal genus of 2 or 3 species, only the following in North America. Type species: Coelo-glossum viride (L.) Hartm.
Orchis bracteata Willd. Sp. PI. 4: 34. 1805.
Habenaria viridis var. bracteata Reichenb. Ic. Fl. Germ.
Stem slender or stout, leafy, 6'-2° high. Leaves lanceolate, ovate or oval, or the lowest sometimes obovate, obtuse or acute, 2'-5' long, the upper much smaller; bracts longer than the ovaries, the lower ones 2 or 3 times as long; spike 3'-5' long, loosely flowered; flowers green or greenish; sepals ovate-lanceolate, spreading, dilated or somewhat gibbous at the base, about 3" long; petals very narrow, sometimes threadlike; lip 3"-4" long, oblong-spatulate, 2-3-toothed or lobed at the apex, more than twice as long as the white sac-like spur; anther-sacs divergent at the base.