OECHIDACEAE. 107 



Order 1. ORCHIDALES. 

 Family 1. ORCHIDACEAE Lindl. Orchid Family. 



Anthers 2; lip a large inflated sac. 1. Cypripedium. 



Anther solitary. 



Pollinia with a caudicle, which is attached at the base to a viscid disk 

 or gland. 

 Glands enclosed in a pouch. 2. Galeorchis. 



Glands not enclosed in a pouch. 



Lip not fringed nor cut-toothed. 



Valves of the anthers dilated at the base enclosing the 



glands below. 3. Perularia. 



Valves not dilated at the base. 4. Gijmnandeniopsis. 



Lip fringed or parted and cut-toothed. 5. Blephariglottis. 

 Pollinia not produced into a cinuUcle (except apparently in ISio. 16). 

 Pollinia granulose and powdery. 



Flowers comparatively large, solitary or few ; anthers incum- 

 bent on a long column. 

 Leaves not grass-like ; lip free. 

 Flowers terminal; lip crested. 



Leaves alternate. (i. Fogonia. 



Stem-leaves whorled. 7. Isotria. 



Flowers axillary ; lip not crested. 8. Triphoru. 

 Leaves grass-like. 



Flowers solitary, terminal; lip adherent to the base 



of the column. 9. Arethusa. 



Flowers racemose; lip free. 10. Limodorwm. 



Flowers small, numerous, in spikes or racemes : anthers erect, 

 jointed to a short column. 

 Leaves green, borne on the stem. 



LeaA'es alternate; spike mostly twisted. 



11. Gyrostachys. 

 Leaves 2, opposite; spike not twisted. 



12. Listera. 

 Leaves white-reticulated, basal. 13. Peramium. 



Pollinia smooth and waxy. 



Plants with eorms or solid bulbs, rarely with coralloid roots; 

 leaves basal or cauline. 

 Leaves unfolding before or with the flowers. 



Leaf cauline ; lip ovate or auricled at the bnse. 



14. Achroanthes. 

 Leaf or leaves basal. 15. Leptorchis. 



Leaf 1, basal, unfolding after the flowering time. 

 Flowers long-spurred; lip 3-lobed. 



16. Tipularia. 

 Flowers not spurred ; lip 3-ridged. 



17. Aplectrum. 

 Plants with coralloid roots, bulbless; the leaves reduced to 



scales. 18. Corallorliiza. 



1. CYPEIPEDIUM L. Lady's Slippek. 



Plant 2-leaved ; scape 1-flowered. 1. C. acaule. 



Stem leafy to the top, 1-several-flowered. 



Lip 3-.5 cm. long, vertically flattened, pale yellow. 2. C. hirsutum. 



Lip 1.5-3 cm. long, laterally flattened, bright yellow. 



3. C. parviflorum. 



1. Cypripedium acaule Ait. Moccasin Flower. M. p. 291. Sandy or rocky 

 woods. Spring. 

 Bucks— TuWytowii (Br.), Durham, Buckingham Valley (Fr.). Mnitt- 



