PoGONiA. CXL. ORCHIDACE^. 535 



/?. (O. incisa. WUUL) Lateral petah subdentate, terminal one incisely den- 

 tate ; spur subulate. 



18. O. LEucoPH^A, Nutt. White-Jlowered or Prairie Orchis. 



St. leafy; Ivs. lanceolate, tapering to a narrow, obtuse point, channeled; 

 bracts shorter than the ovaries ; roc. oblong ; sep. roundish-oblong, acutish ; 

 lateral petals obovate, denticulate; Up 3-parted, flabelliform, segments deeply 

 fimbriate; spur subulate-clavate, curved, twice as long as the ovary. — Wet 

 prairies, Ohio, Ind. ! 111. Stem 1— 3f high. Leaves 2— G' long. Raceme about 

 12-flowered. Sepals and spur yellowish, petals white. Ovary curved, 1' long. 



19. O. GRANDiFLORA. Bw. (Habeuaria. T(/rr. Platanthera fimbriata. 

 Lindl.) Large-Jlowcring Orchis. — Lov:er Ivs. oblong, oval, obtuse, iippcr 



ofies very naTTOw; bracts shorter than the ovary; roc. oblong; lip dependent, 

 twice as long as the petals, 3-parted, the segments cuneiform and fimbriate, the 

 middle one largest, with connivent fimbriae ; lateral pet. fimbriate ; spur ascend- 

 ing, clavate, longer than the ovary. — A superb plant, considered the most beau- 

 tiful of the genus, in wet meadows, N. H. ! Can. Stem 2— 3f high, thick, hol- 

 low, with several sheathing bracts at base. Leaves 2 or 3 principal ones, 4 — 1' 

 by 1 — 2', upper ones linear, an inch or two long. Flowers very large, purple, 

 in a terminal raceme, 3 — 6' long. Middle seg. of the lip nearly semicircular, 

 twice as long as the lateral ones. June. 



Section 3. Pollen powdery, or consisting of loosely cohering 



granules. 



8. A RE THUS A. Swtz. 

 Arethtisa was a fabulous nymph of Diana, who was transformed into a foimtain. 



Perianth with its segments cohering at base ; lip spurless, adnate 

 to the column at base, deflected at the end and bearded inside ; pollen 

 angular. — Small plants^ inhabiting ^oet places. 



A. BCLBosA. Bulbous Arcthum. 



Leafless ; rl. producing a globular tuber ; scape sheathed, 1-flowered. — 

 This beautiful and interesting plant is found only in wet meadows and swamps, 

 Can. to Va. Stem 6 — 12' high, invested with about 3, long, loose sheathes with 

 lanceolate points, the upper ones rarely at length produced into a short, linear- 

 spatulate leaf At the top is a single, large, fragrant flower of a rich purple 

 color. A little below the base of the flower is a small spathe of 2 unequal 

 bracts. June. 



9. POGONIA. Brown. 



Gr. TTwywj/, beard ; in allusion to the bearded lip. 



Perianth with its leaflets distinct ; lip sessile or unguiculate, 

 cucuUate, bearded inside ; pollen farinaceous. 



1. P. opniOGLo.'?s-oiDF..s. Br. TArethusa. Linn.) 



lit. fibrous ; St. lurnishcd with an oval-lanceolate leaf and a foliaceous 

 bract near the flower ; lip fimbriate. — An interesting plant, much taller than 

 the bulbous Arethu.sa, found in swamps and muddy shores, Can., N. Eng. to 

 Car. and Ky. The stem is very slender, 9 — 16' high, with 2 remote leaves, the 

 one placed about midway, 2 — 3' long, lanceolate, acute, sheathing at the base; 

 the other (a bract ?) much smaller, situated near the flower. Flower large, 

 nodding, pale purple. Lip lung as petals and sepals (}'). June. 

 . 2. P. vKUTiciLi.ATA. Nutt. (Arcthusa. Willd.) 



Lrs. 5, oblong-lanceolate, veiticillate ; /Is. .solitary, the 3 outer petals very 

 long, linear, inner ones shorter, lanceolate, obtuse; //>'3-lobed, the middle lobes 

 undulate. — Swamps. Stem 8-— 12' high, with a whorl of leaves near the top 

 and a flower 1—2' above it. Leaves IJ' long, i as wide, abruptly acuminate. 

 The flower is remarkable fur its .sepals being about 2' long, very" narrow, and 

 of a greenish-brown color. Lip crested in the middle. July. 



3. P. PENDiLA. Lindl. (Triphora. Nutt. Arelhusa. WiUd.) 



7?/. tulx'rous ; .^/. lealy, aiiout 3-fl()wered at the top ; lis. clasping, ovale, 

 alternate; /7<. nxillarv, nodding' ; /'/' <Mitire, scabrous, n<«' bn;n>i''il : fr pi-ndn- 



