ORCHID ACE & 625 



only the anther opposite to the lower sepal perfect and 2 rudi- 

 mentary lateral ones, in Cypripedium the lateral ones perfect, 

 the third sterile. Anthers 2-celled. Pollen more oi- less coher- 

 ent in 1-4 masses, rarely wholly granular. Stigma oblique and 

 concave, mostly viscous, the upper margin often produced into 

 an erect beak. Capsule coriaceous or membranceous, dehiscing 

 usually by 3 placentiferous valves which separate from the per- 

 sistent midveins of the carpels. Seeds very numerous, scobi- 

 porm, without albumen. 



Trire i Anther one, resting like a lid upon the column, de- 

 ciduous. Pollen masses 4, smooth and waxy. 



1 Calypso Scape solitary and 1-flowered, from a solid bulb, with a single 



green leaf: lip saccate: column broadly winged. 



2 Corallorhiza Stems one to several from a branched coral-like root : 



leaves ail reduced to scale-like bracts: flowers in a terminal raceme, 

 spurred or gibbous at base : lip expanded or concave, bilamellate-crest- 

 ed: column semiterete. 



Tribe ii Anther one, connate with the column and resting 

 upon its face just above the stigma. Pollen masses 2, of coarse 

 grains united by an elastic web. 



3 Habenaria Stems one to several from a solid corm : flowers numerous, 



in a terminal raceme : lip flat, spurred. 



Tribe hi Anther 1 3 erect and sessile or nearly so upon the top 

 of the column, more or less covering and declinate upon the back 

 of the stigma. Pollen masses 2 or 4, of loosely cohering grains. 



4 Gyrostachys Stems one to several from fleshy fascicled roots : flowers 



numerous in a twisted spike: lip flat, the base embracing the short 

 column. 



5 Peraniium Stem solitary from a somewhat creeping rootstock : flowers 



several in a terminal spike; lip saccate, entire, free from the column. 



6 Listera Stem solitary from a fascicle of fleshy-fibrous roots with a pair 



of sessile leaves in the middle ; flowers rather few, in a terminal raceme : 

 lip flat. 2-lobed. 



7 Epipactis Stems stout, leafy, several from fleshy-fibrous roots : lip 



concave, somewhat jointed in the middle and auriculate at base: 

 anther sessile behind the beaked stigma. 



8 Cephalanthera Stems stout, from a somewhat creeping rootstock : 



flowers in a terminal raceme: lip concave and auriculate at base: an- 

 ther shortly stipitate : stigma beakless. 



Tribe iv Perfect anthers 2, lateral. Pollen pulpy-granular. 



9 Cypripedium Stems leafy, from more or less creeping rootstocks : 



flowers mostly few, in a terminal raceme : lip an inflated sac. 



Tribe 1 Malaxideee Lindl. Orch. S Herbs with simple stems 

 without green foliage, or a sxngle green radical leaf. Anther one, 

 terminal and resting like a lid vpon the column, deciduous. Pollen 

 masses 4, smooth and waxy. 



