320 ORCHID ORDER 



1. Flowers yellow, usually solitary 



a. Lip 1.5-3 in. long C.pubescens 



b. Lip 1.5-3 cm. long C. parviftorum 



2. Flowers purple or yellow, 2-several in a cluster ; 



leaves 2, opposite C. Knightae 



Epipactis Robert Brown 1813 Helleborine 

 (Greek name of a plant) 



Sepals and petals separate, similar, greenish, purple-veined, lip broad, 

 concave below, constricted near the middle, the upper part broad and petal- 

 like, column short, erect, pollinia 2-parted ; flowers few in leafy-bracted, 

 terminal racemes ; leafy-stemmed perennial from a creeping root-stalk. 

 Stems 1-3 ft. high; leaves ovate to lanceolate; sack- 

 like base of the lip with wing-like margins E. gigantea 



Limnorchis Rydberg 1900 Green Orchid 



(Gr. limne, lake, orchis, orchid) 



Sepals and petals greenish, free, spreading, similar, lip linear or lance- 

 olate, entire, the spur shorter to longer than the lip, column very short; 

 flowers greenish to white, in terminal spikes or racemes ; leaves alternate, 

 lanceolate to ovate ; perennial with fibrous or tuberous roots. 



1. Flowers white; spur club-shaped, shorter than 



the lip L. boredlis 



2. Flowers greenish or greenish-purple 



a. Lip 4-5 mm. long, not exceeded by the spur 



(1) Spur shorter than the lip L.stricta 



(2) Spur equalling the lip L.viridiHora 



b. Lip 6-8 mm. long, exceeded by the spur L.'sparsiflom 



Listera Robert Brown 1813 Twayblade 

 (Named for Lister, an English botanist) 



Sepals and petals nearly alike, spreading or reflexed, free, anther with- 

 out a lid, joined with the column, pollinia 2 ; flowers greenish yellow to 

 purplish, spurless, in terminal racemes ; leaves 2, opposite, near the middle 

 of the stem, 1-2 small scales at the base of the stem; small herb with fibrous 

 roots. 



1. Stems sticky-hairy; lip wedge-shaped, 2-lobed L. convallarioides 



2. Stems smooth ; lip linear, 2-cleft L. cor data 



