OKCHIDACE^. (OECHIS FAMILY.) 109 



* Anther one {hut distinctly/ 2-celled,) 



Anther adnate to the face of the stigma Habenaria. . 1 



Anther adnate to the back of the stigma. 



Lip free from the column Epipactis. 2 



Lip adherent to the base of the coh;mn Spirantlies. 3 



Anther like a lid over the stigma. (See Addenda.) 



Lip with a spur adherent to the ovary CoraUorhiza, 4 



* * Anthers two, one on each side of the column. 

 Lip a conspicuous inflated sac Cypripedium. 5 



1. HABENARIA, Willd., R. Br. Eei.v Orchis. 

 Flowers ringent; the sepals and petals similar; lip spurlike; ovary twisted. Swamps. 



1. H. elegaiis, Lindl. The greenisli flowers in a dense spike; spur filifonn. 



2. H. leucostacliys. Stems 1 to 3 feet high; spikes 4 to 18 inches long; flowers 

 large, greenish, the spur longer than the entire lip, 6 to 9 lines long. 



2. EPIPACTIS, Hall. 



Petals and sepals similar, spreading, nearly equah Lip oblong, the upper portion con- 

 cave and fleshy, the lower jjetaloid, imdivided. Stigma square, projecting downward. 



1. E. gigantea, Dougl. Leaves plicate; flowers brownish or purplish, x^ediceled in 

 a spicate raceme, pubescent. Borders of streams. 



3. SPIRANTHES, Richard. Ladies' Tresses. 



Flower oblique on the ovary, the 3 upper segments erect, and more or less cohering, 

 the bases of the lip covered by the remaining two segments, and bearing a pair of callosi- 

 ties. Flowers in a twisted spike, small, green or greenish white. 



S. RonianzofHana, Cham. Smooth, 4 to 18 inches high, leafy; dense spike 3-ranked, 

 bracteate; perianth, white, 4 lines long; petals and sepals incurved; callosities small and 

 smooth. 



S. porrifolia, Lindl. Similar; flowers smaller, callosities larger. 



4. CORALLORHIZA, Haller. Coral-root. 



Perianth-segments nearly equal, the lower one (lip) bearing at the base a pau' of pro- 

 jecting ridges. Brownish or yellowish, leafless herbs with sheathing bracts; flowers in 

 spiked racemes. 



1. C. Bigelovii, Wat. Plant purplish, simple stems 12 to 18 inches high, bearing 20 

 or 30 flowers in a crowded sj)ike, on very short pedicels; perianth-segments 4 to 6 lines 

 long, marked with 3 dark stripes; capsules reflexed. 



5. CYPRIPEDIUM, L. Lady's Slipper. 

 Sepals spreading, distinct, or two lower united. Petals resembling the sepals. Lip a 

 large inflated sac. Style bearing on each side a short stamen, the stigma covered by a 

 triangular petal-like sterile stamen, which bends down over it. 



