148 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



KEY TO THE SPECIES. 



Outer bracts of the inflorescence about twice as long as the inner 1. S. campestre. 



Outer bracts of about the same length as the inner. 



Perianth 7 to 10 mm. lo»g; plants somewhat glaucous, the stems 

 clustered; bracts broad, 10 to 20mm. long; stems flexuous, 



often ascending 2. S. dernissum. 



Perianth 10 to 14 mm. long; plants more slender, bright green, 

 the stems mostly solitary, erect, straight; bracts 16 to 32 

 mm. long 3. S. occidentale. 



1. Sisyrinchium campestre Bicknell, Bull. Torrey Club 26: 341. 1899. 



Type locality: "^Msconsin to North Dakota, south to Louisiana, Oklahoma and 

 the mountains of New Mexico." 



Range: As under type locality. 



New Mexico: Chama; Santa Fe and Las Vegas mountains; Sierra Grande; Sacra- 

 mento Mountains. Transition Zone. 



2. Sisyrinchium denussum Greene, Pittonia 2: 69. 1890. 



Type locality: "In moist meadows at the base of Bill Williams Mountain 

 Arizona, and also near Flagstaff." 



Range: Arizona to western Kansas. 



New Mexico: Las Vegas; mountains west of Grants Station; Zuni; Barranca; Mogo- 

 Uon Mountains; Black Range; Chavez; Socorro; WTiite Mountains. Meadows, in the 

 Transition Zone. 



3. Sisyrinchium occidentale Bicknell, Bull. Torrey Club 26: 447. 1899. 

 Type locality: "Idaho and Nevada to Colorado and North Dakota." 

 Range: As under type locality. 



New Mexico: Near Pecos; Iron Creek, Mogollon Mountains; north of EI Vado. 

 Upper Sonoran Zone. 



3. IRIS L. Blue flag. 



Plants 30 to 70 cm. high, with long, flat, somewhat glaucous leaves arising from a 

 thickened rootstock; flowers large, very showy, sweet-scented, pale blue. 



1. Iris inissouriensis Nutt. Journ. Acad. Phila. 7: 58. 1834. 

 Type locality: " Towards the sources of the Missouri." 

 Range: British America south to California, Arizona, and New Mexico. 

 New Mexico: Santa Fe and Las Vegas mountains; Sandia Mountains; Tunitcha 

 Mountains; Chama; Sierra Grande; Manguitas Spring; Black Range; White and 

 Sacramento mountains. Meadows, in the Transition and Canadian zones. 



Order 15. ORCHID ALES. 



28. ORCHIDACEAE. Orchis Family. 



Herbaceous plants, perennial by bulbs or tliickened roots, sometimes parasitic; 

 leaves entire, from mere sheathing bracts to broadly ovate; flowers sometimes con- 

 spicuous, in ours usually small, of bizarre fomis especially adapted to insect pollina- 

 tion; corolla of two similar lateral petals and a third (the lip or labellum) very different 

 one, this frequently spurred or saccate; stamens gynandrous, with usually only one 

 anther; pollen in small coherent masses (pollinia); ovary inferior; fruit a capsule. 



