HO ORCHIDACEAE. 



Flowers green or sometimes purple-tinged; spur clavate 

 much shorter than the lanceolate lip; spike long and 

 dense. L. stricta. 



Flowers white. 



Spur clavate, usually shorter than the lip. L. dilatata. 



Spur not clavate, longer than the lip. 



Spike moderately dense; spur acutish. L. leucostachys. 



Spike very dense; spur obtuse. L. leucostachys robusta. 



Limnorchis stricta (Lindl.) Rydb. Stems stout, leafy, 5CMOO cm. tall; 

 leaves lanceolate, acuminate, 1015 cm. long, gradually diminishing upward 

 into the bracts; spike slender, 20-30 cm. long, loose, the lower flowers remote; 

 bracts narrowly lanceolate, exceeding the lower flowers, equalling the upper 

 ones; sepals 3-nerved; lip linear, thick, as long as the spur, which is inflated and 

 very obtuse at the tip. 



In swamps, common. 



Limnorchis dilatata (Pursh) Rydb. Stems slender, 20-40 cm. high; leaves 

 linear-lanceolate, 8-20 cm. long; flowers white; lip broadly dilated at base, 

 about as long as the blunt spur. 



* n wet a lpi ne meadows, rare in our limits. 



Limnorchis leucostachys (Lindl.) Rydb. Stem strictly erect, 30-90 cm. 

 high, from a fusiform tuber; leaves lanceolate, acute, the upper ones smaller; 

 spike 6-30 cm. long, usually rather dense; bracts acuminate, equalling or 

 exceeding the ovary; sepals 5-6 mm. long, the upper one broader; lip lanceolate, 

 6-7 mm. long; spur 10-12 mm. long, slender, acute. 



In marshes, common. 



Limnorchis leucostachys robusta Rydb. Spike dense; spur obtuse. 

 More common than the species and in similar places. 



139. PIPERIA. 



Much like Limnorchis in the form of the flowers but the true 

 leaves basal or nearly so, the cauline usually small or bract-like; 

 flowers small, white or greenish; sepals ovate, 1-nerved, sub- 

 equal; petals and lip of very much the same shape and slightly 

 smaller and darker than the sepals; column very short; anther 

 very 'large; cells parallel, the gland very small. 



Spur short, slightly exceeding the lip. P. unalaschensis. 



Spur slender, 2-3 times as long as the lip. 

 Lip ovate to ovate-lanceolate. 



Spike very dense; stems stout, 20-30 cm. high. P. michaeli. 



Spike usually loose; stems 40-70 cm. high. P. elegans. 



Lip linear to lanceolate. 



Spike dense; lip 6 mm. long; spur 15-18 mm. long. P. multiflora. 

 Spike loose; lip 45 mm. long; spur 8-10 mm. long. P. leptopetala. 



Piperia unalaschensis (Spreng.) Rydb. Stems stout, 20-40 cm. tall, 

 leafy at base, bractsate above; leaves 2-3, oblanceolate, obtuse, about 15 cm. 

 long, usually withering before the flowers bloom; spike narrow, rather dense, 

 8-15 cm. long; bracts triangular, acute or acuminate, shorter than the ovary, 

 a few along the stem below the spike; flowers small, greenish; sepals and petals 

 lanceolate, 1-nerved, 1.5-2 mm. long; lip scarcely exceeding the petals; spur 

 curved, about 3 mm. long; capsule oblong, sessile. 



Common in open woods. 



