OKCHIDACEAE 317 



oblong, longer than the petals, erose or crenulate : spur straight, longer than the lip. 

 [Gymnadenia flava (Nutt. ) LindL] 



In pine-land swamps, New Jersey to Florida and Louisiana. Summer. 



11. GYROSTACHYS Pers. 



Herbs, with tuberous or fleshy-fibrous roots. Stems more or less completely clothed 

 with the sheathing leaf-bases. Leaves alternate, sometimes mainly basal, those on the 

 upper part of the stem reduced to sheathing scales. Flowers in terminal spiral spikes of 

 1-3 rows. Perianth not showy. Sepals distinct or coherent at the top or united to the 

 nearly similar lateral petals. Lip concave, erect, sessile or contracted into a claw, bearing 

 2 callosities near the base. Column oblique from the top of the ovary, arched, merely ad- 

 herent to the lip and often embraced by it. Anther erect, the back of the column without 

 a lid. Pollen-masses one in each sac. Stigma prolonged into a beak and 2-cleft, covering 

 the anther, stigmatic beneath. Capsules erect. [Spiranthes L. C. Rich. J LADIES' TRESSES. 



Flowers alternate, forming a one-sided spike by the twisting of the rachis. 

 Lip oblong or nearly so. 



Leaves with blades at the base of the stem or near it, fugacious ; blades oblong, elliptic or ovate. 

 Lip white': root solitary. 1. O. simplex. 



Lip green in the middle : roots several. 2. G, gradlis. 



Leaves with blades extending up the stem, persistent ; blades linear. 



Lateral sepals lanceolate. 3. G. praecox. 



Lateral sepals narrowly linear-lanceolate. 



Lip lacmiate near the tip. 4. G. laciniata. 



Lip merely crisped or erose. 



Bracts scarious-margined, ovate : lower leaves with very narrow 



elongated blades and narrow bases. 5. G. lincaris. 



Bracts not scarious-margined, lanceolate or oblong-lanceolate : lower 

 leaves with relatively short and broad blades and broad loose 

 sheathing bases. 6. G. xyridtfolia. 



Lip ovate to rhombic. 



Leaves with blades only 1 or 2, or none : Floridian species. 7. G. brevtfolia. 



Leaves with blades 3-6 : Texan species. 8. G. Reverchonii. 



Flowers 2-ranked, forming a cylindric spike : rachis barely twisted. 

 Lip merely crisped at the apex, not lobed. 

 Lip oblong or nearly so. 



Lip less than 5.5 inm. long. 9. G. parviflora. 



Lip over 6 mm. long. 



Lip with a cuneate base and 2 stout reflexed callosities. 



Corolla white : spike blunt : the lower bracts shorter than the 



corollas. 10. G. cernua. 



Corolla yellowish : spike acute : the lower bracts longer than the 



corollas. 11. G. ochroleuca. 



Lip with a truncate base and 2 small spreading callosities. 12. G. plantaginea. 



Lip with a dilated base or both base and apex dilated. 



Upper part of the lip oblong at least not dilated. 13. G. odorata. 



Upper part of the lip dilated. 



Leaf-blades linear : dilated upper portion of lip oval or suborbicular. 14. G. vernalis. 

 Leaf-blades broader : dilated upper portion of lip ovate. 15. G. constricta. 



Lip 3-lobed at the apex. 16. G. triloba. 



1. Gyrostachys simplex (A. Gray) Kuntze. Koot solitary, tuber-like : stems very 

 slender, 1-3 dm. tall, furnished with few often deciduous scales : leaf -blades ovate or 

 oblong, 1-3 cm. long, disappearing before flowering time : spike slender, 1-5 cm. long, 

 5-8 mm. thick, glabrous: perianth white, 2-3 mm. long : lip broadly oblong, 2.5-3 mm. 

 long, crisped at the apex, with a short claw-like base and 2 basal nipple-like callosities : 

 capsules 4-5 mm. long. 



In sandy soil, Massachusetts to Florida. Summer and fall. 



2. Gyrostachys gracills (Bigel. ) Kuntze. Boots coarse, clustered : stems scape-like, 

 2-6 dm. tall, glabrous or pubescent above, furnished with remote clasping scales: leaf- 

 blades oblong, elliptic or ovate-lanceolate, 1.5-5 cm. long, short-petioled : spike slender, 

 3-15 cm. long, 8-10 mm. thick : perianth white, 4-5 mm. long : lip shorter than the sepals, 

 oblong, undulate or crenulate near the apex, green in the centre, otherwise hyaline and 

 white, with 2 nipple-shaped callosities at the truncate base : capsules slightly curved, 4-5 

 mm. long. 



In open woods and on slopes, Nova Scotia to Minnesota, Florida, Louisiana and Kansas. Summer 

 and fall. 



3. Gyrostachys praecox (Walt.) Kuntze. Boots tuberous, several: stems 2-8 dm. 

 tall, leafy to the top : leaf -blades linear, attenuate from the narrow sheathing base, or some- 

 times slightly dilated toward the middle, 5-30 cm. long, or reduced to sheathing scales 

 above : spike spirally twisted, 3-10 cm. long : bracts more or less imbricated : perianth 

 whitish or yellowish, pubescent without, 6-8 mm. long, curved and slightly nodding : 



