Contents Introduction Amerorchis rotundifolia   Small round-leaf orchid Arethusa bulbosa   Dragon's-mouth Calopogon tuberosus   Grass-pink Calypso bulbosa   Fairy-slipper Coeloglossum viride   Long-bracted orchid Corallorhiza maculata   Spotted coralroot Corallorhiza striata   Striped coralroot Corallorhiza trifida   Early coralroot Cypripedium acaule   Moccasin-flower Cypripedium arietinum   Ram's-head lady's-slipper Cypripedium candidum Small white lady's-slipper Cypripedium parviflorum var.makasin   Small yellow lady's-slipper Cypripedium parviflorum var.pubescens   Large yellow lady's-slipper Cypipedium passerinum   Sparrow-egg lady's-slipper Cypripedium reginae   Showy lady's-slipper Goodyera repens   Lesser rattlesnake-plantain Goodyera tesselata   Tesselated rattlesnake-plantain Liparis loeselii   Loesel's twayblade Listera borealis   Northern twayblade Listera cordata   Heart-leaved twayblade Malaxis monophyllos   White adder's-mouth Malaxis paludosa   Bog adder's-mouth Malaxis unifolia   Green adder's-mouth Platanthera aquilonis   Tall leafy green orchid Platanthera dilatata   Tall leafy white orchid Platanthera hookeri   Hooker's orchid Platanthera lacera   Ragged fringed-orchid Platanthera obtusata   Blunt-leaf orchid Platanthera orbiculata   Large round-leaved orchid Platanthera praeclara   Western prairie fringed-orchid Platanthera psycodes   Purple fringed-orchid Pogonia ophioglossoides   Rose pogonia Spiranthes lacera   Northern slender ladies'-tresses Spiranthes magnicamporum   Great plains ladies'-tresses Spiranthes romanzoffiana   Hooded ladies'-tresses