OECHIDACEAE 323 



sessile, erect from the base of the column, crested. Anther terminal, stalked, with paral- 

 lel sacs. Pollen-masses 2 in each sac, powdery-granular, without tails. Capsule erect, 

 pedicelled. 



1. Isotria verticillata (Willd.) Raf. Foliage glabrous. Leaves wanting in the flow- 

 ering plant or represented by several basal scales : scapes 2-4 dm. tall, topped by a whorl 

 of 4-5 bracts : bracts thickish ; blades elliptic to oval or often broadest a little above the 

 middle, abruptly acuminate, sessile : peduncles erect or ascending, shorter than the bracts : 

 sepals linear or linear-filiform, 2.5-5 cm. long, spreading : lateral petals linear, 1.5-2 cm. 

 long, erect, entire : lip nearly erect, 3-lobed, crested, 1-1.5 cm. long : capsule oblong, 2-3 

 cm. long. [Pogonia verticillata (Willd.) Nutt.] 



In woods, Ontario to Wisconsin, Florida and Alabama. Spring. 



20. POGONIA Juss. 



Caulescent herbs, with slender or cord-like roots and glabrous foliage. Leaves alter- 

 nate, sometimes solitary on the stem, sessile, or the basal with long petioles. Flowers soli- 

 tary or 2 at the top of the stem. Perianth commonly highly colored. Sepals distinct, 

 erect or ascending. Petals distinct, the lateral ones about as long as the sepals or shorter. 

 Lip erect from the base of the column, sometimes fringed, crested. Column club-shaped, 

 elongated. Anther terminal and stalked on the back of the column : sacs parallel. Pollen- 

 masses 2, one in each sac, powdery-granular, tailless. Stigma disk-like, below the anther. 

 Capsule erect, ribbed. 



Sepals and lateral petals about equal in length : lip bearded and crested. 1. P. ophioglossoides. 



Sepals much longer than the lateral petals : lip merely crested. 2. P. divaricata. 



1. Pogonia ophioglossoides (L. ) Ker. Eoots fibrous, cord-like. Foliage green: 

 stems 2-5 dm. tall : leaves basal and 1 or 2 on the stem ; blades various, those of basal 

 leaves oblong-elliptic, 8-13 cm. long, pinched at the apex, tapering into a slender petiole 

 longer than the blade ; those of the stem oblong-lanceolate to elliptic, 3-8 cm. long, clasping : 

 bracts similar to the leaves, but smaller : flowers solitary or several at the top of the stem : 

 perianth rose-colored, somewhat nodding : sepals linear-elliptic or oblong, 1.5-2 cm. long, 

 acute : lateral petals elliptic or oblong-cuneate, about as long as the sepals : lip spatulate 

 or linear-spatulate, fimbriate, crested : capsules oblong, 1.5-2 cm. long. 



In swamps and meadows, Newfoundland to Ontario, Kansas, Florida and Alabama. Spring 

 and summer. 



2. Pogonia divaricata (L. ) R. Br. Roots fibrous, cord-like. Foliage glaucescent : 

 stems 2-6 dm. tall, strict : leaves basal, and 1 or 2 on the stem : blades narrowly oblong 

 or oblong-lanceolate, 5-15 cm. long, obtuse or acutish, entire, sessile and partly clasping : 

 bracts similar to the leaves but smaller : flowers normally solitary at the top of the stem : 

 perianth deep pink or lilac : sepals linear or nearly so, 2.5-5 cm. long : lateral petals ob- 

 long to narrowly elliptic or elliptic-oblanceolate, acuminate, shorter than the sepals : lip 

 about as long as the petals, half-tubular, 3-lobed : capsule. 



In moist soil, New Jersey to Florida and Alabama. Summer. 



21. TRIFHORA Nutt. 



Caulescent herbs, with fleshy tubers. Stem simple. Leaves alternate : blades thick, 

 entire. Flowers axillary. Sepals and lateral petals free, ascending, nearly equal. Lip 

 erect, neither crested nor spurred, 3-lobed, slightly clawed. Column elongated, club- 

 shaped at the summit. Anther terminal, stalked on the back of the column, with parallel 

 sacs. Pollen-masses 2, granular-powdery, 1 in each sac, without tails. Stigma a flattened 

 disk below the anther. Capsules stalked, drooping. NODDING-CAP. 



1. Triphora trianthophora (Sw. ) Rydb. Roots tuberous : stems sometimes clustered, 

 5-30 cm. high : leaf -blades, 2-10, suborbicular to ovate, 5-20 mm. long, clasping : flowers 

 2-7 or sometimes solitary, axillary : perianth pedicelled, soon drooping, pale purple, 10- 

 16 mm. long : sepals and lateral petals nearly equal, converging, obtuse, rather elliptic : 

 lip 3-lobed, about as long as the lateral petals, narrowed into a short claw : capsules oval, 

 10-12 mm. long, drooping. [Pogonia pendula Lindl.] 



In rich woods, Canada to Wisconsin and Kansas, south to Florida. Summer. 



22. EPIPACTIS R. Rr. 



Caulescent herbs, with fibrous roots. Leaves alternate : blades plaited, clasping or 

 partly so. Flowers several in conspicuously bracted terminal racemes. Sepals and petals 



