ORCHIDACEJE. (ORCHIS FAMILY.) 



* * Leafless, with coralloid roots ; whole plant brownish or yellowish ; flowers racemose. 



6. Corallorhiza. Polliuia 4, in 2 pairs. Flower gibbous or somewhat spurred, and lip 



with 1 -:', ridges ; sepals and petals 1 - 3-nerved. 



7. Hexalectris. Polliuia 8, united. Flower not gibbous ; sepals and petals several- 



nerved : lip with 5-6 ridges. 



Tribe II. NEOTTIE^E. Anthers erect upon the back of the column at the summit, 

 or terminal and opercuhir. Pollinia granular or powdery, more or less cohering in 2 or 4 

 delicate masses, and attached at the apex to the beak of the stigma. 



* Anthers without operculum, erect upon the back of the short column. Flowers small, in 



spikes or racemes. 



8. Listera. Stem from a fibrous root, 2-foliate. Lip flat, 2-lobed. 



9. Spiranthes. Stems leafy below, from tuberous-fascicled roots. Flowers 1-3-ranked 



in a twisted spike. Lip embracing the column below, with 2 callosities at base. 



10. Goodyera. Leaves radical, white-reticulated. Lip entire, free from the column, 



saccate, without callosities. 

 * * Anther operculate, erect and jointed upon the short column. Stem stout, very leafy. 



11. Epipactis. Flowers racemose ; perianth spreading; lip dilated above. 



* * * Anther terminal, operculate, incumbent ; column elongated. Stem scapose or few- 



leaved ; flowers large, solitary or few. 



12. Arethusa. Leaf and flower solitary. Lip bearded, its base adherent to the linear 



column. Pollinia 4. 



13. Calopogon. Leaf solitary, grass-like. Lip bearded, stalked, free. Column winged at 



the apex. Pollinia 4. 



14. Pogonia. More or less leafy. Lip crested, free. Column clavate. Pollinia 2. 



Tribe III. OPHBYDE^E. Anther without operculum, the cells adnate to the top of 

 the column and often continuous with the beak of the stigma. Pollinia 2, of coarse 

 grains united by an elastic web, each attached at base by a stalk to a viscid gland. 

 Flower (in ours) ringent and spurred, spicate upon a leafy stem. 



15. Orchis. The two glands or viscid disks enclosed in a common pouch. 



16. Habenaria. The two glands naked, either approximate or widely separated. 

 Tribe IV. CYPRIPEDIE^E. Perfect anthers 2, lateral, the sterile one forming a 



dilated fleshy appendage above the terminal stigma. Pollen granular, not in masses. 



17. Cypripedium. Stems more or less leafy. Perianth spreading ; lip an inflated sac. 



1. MICROSTYLIS, Nutt. ADDER'S MOUTH. 



Sepals oblong, spreading. Petals thread-like or linear, spreading. Lip au- 

 ricled or ovate at base, not tubercled, entire or nearly so. Column very small, 

 terete, with 2 teeth or auricles at the summit and the erect anther between 

 them. Pollen-masses 4, in one row (2 in each cell), cohering by pairs at the 

 apex, waxy, without any stalks, threads, or gland. Low herbs, from solid 

 bulbs, producing simple stems, which bear in our species a single leaf and a 

 raceme of minute greenish flowers. (Name composed of /j.iKp6s, small, and 

 <TTV\LS, a column or sti/le.) 



1. M. monophyllos, Lindl. Slender (4-6' high); leaf sheathing the 

 base of the stem, ovate-elliptical; racemes spiked, long and slender; pedicels 

 not longer than the flowers lip long-pointed. Cold wet swamps, N. New Eng. 

 to Penn., N. Intl., Minn., and northward. July. (En.) 



2. M. ophioglossoides, Nutt. Leaf near the middle of the stem, 

 ovate, clasping ; raceme short and obtuse ; pedicels much longer than the flowers ; 

 lip truncate-3-lobed at the summit, the middle lobe very small. Low moist 

 ground, N. Scotia to Fla., west to Minn, and Mo. July. Polliuia (at least 

 sometimes) only 1 in each cell. 





