66 ORCHIDACEAE (ORCHID FAMILY) 



EE. Plant 2-flowered; flowers white, blotched and striped with yellow and purple; 

 outer perianth segments 3~3-5 cm. long; capsule globose. C. I. tenuis 



DD. Leaves evergreen; bracts 5-7.5 cm. long. 



F. Flowers yellow; perianth tube less than 2.5 cm. long, funnelform; spathe bracts 

 short-acuminate. U. I. bracteata 



FF. Flowers white to yellow, with blue veins; perianth tube 5-7.5 cm. long, fili- 

 form; spathe bracts long-acuminate. U. I. chrysophylla 



SISYRINCHIUM (BLUE-EYED GRASS) 



Tufted, slender; stem 2-edged or -winged. Leaves grasslike. Flowers 

 in a terminal umbel, or only i, mostly blue; spathe bracts 2, green or 

 purplish, erect. Perianth segments spreading, alike, mostly aristulate. 

 Filaments united at least at base. Stigmas filiform. Seeds 9-12. Mostly 

 in wet grassy places. (Gk. sisyrinchion = the name of some Flaglike plant.) 



A. Inner bracts exceeding the flowers. 



B. Stem 2-3 mm. wide; perianth 12-14 mm. long, deep blue, with orange yellow 

 eye. W. S. littorale 



BB. Stem 1-1.5 mm. wide; perianth 7-10 mm. long, light blue, without eye. C. 



S. sarmentosum 

 AA. Inner bracts not reaching the tips of the flowers. 



C. Perianth 4-7 mm. long, white or pale; leaves and stem 0.5-1 mm. wide. E. 



S. septentrionale 



CC. Perianth 10-22 mm. long, dark blue; leaves and stem i mm. or more wide 



(except 5. occidental). 



D. Stem usually 2-branched. W. S. biramium 

 DD. Stem always simple. 



E. Outer spathe bracts 3-7 cm. long. W. E. S. macounii 



EE. Outer spathe bracts 1.8-3.8 cm. long. W. E. S. occidental e 



HYDASTYLUS (YELLOW STAR-GRASS) 



Black to purplish when dry ; stem simple, scapose. Leaves linear, wider 

 at base, somewhat equitant. Spathe bracts 2, inclosing membranous 

 scales ; perianth segments not aristulate nor emarginate. Anthers versatile. 

 Capsule more or less 3-angled. (Gk. hydor = water, stylos = a style ; 

 application not clear.) 



A. Perianth 8-10 mm. long; leaves 1-3 mm. wide, mostly very dark in drying; anthers 

 2-2.5 mm. long. W. H. borealis 



AA. Perianth 12-18 mm. long; leaves 2-5 mm. wide, mostly not very dark in drying; 

 anthers 3-4 mm. long. W. H. brachypus 



ORCHIDACEAE (ORCHID FAMILY) 



Herbs, perennial. Leaves parallel-veined, flat. Flowers in a 

 spike or a raceme or solitary, very irregular. Perianth superior, 

 of 6 segments: outer segments 3, alike or nearly so ; 2 of the inner 

 segments alike; the third (lip) unlike the other 2, often quite 

 different, usually larger. Stamens adhering to the style and form- 



