156 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. || 



Range: Washington to New Brunswick, south to CaHforn".a and FU)rida. 

 Specimens examined: West Klickitat County, SuJtsrfor/ 223; Ahnota, Piper 2651. 

 Zonal distribution: Upper Sonoran. 



DTJLICHITJM. 



1. Dulichium arundinaceum (L.) Britton, Bull. Torr. Club 21: 29. 1894. 

 Cyperus arundinaceus L. Sp. PI. 1 : 44. 1753. 

 Schoenus spathaceus L. Sp. PI. ed. 2. 1: 63. 1762. 

 Cyperus spathaceus L. Syst. cd. 12. 2: 735. 1767. 

 Dulichium spathaceum Pers. Syn. 1 : 65. 1805. 

 Type locality: "Habitat in Virginia." 



Range: British Columbia to Nova Scotia, .south to Oregon, Texas, and Florida. 

 Specimens examined: Seattle, Piper 692; Lakeview, Fletl, Septeml)er 20, 1899. 

 Zonal distribution: Humid Transition. 



SCIRPXTS. 



Spikelets solitary, terminal. 



Involucral bract present, not longer than the spikelet. 



Perianth bristles none 1. S. riparius. 



Perianth bristles 6, smooth 2. S. cespitosus. 



Involucral bract 2 to 3 times as long as the spikelet 3. <S. subterminalis. 



Involucral bract wanting 4.5. paucijlorus. 



Spikelets several to many, rarely .solitary. 

 Stems terete. 



Inflorescence apparently lateral, sessile 5. 5. nevadensis. 



Inflorescence umbellate. 



Akenes 2 mm. long, the .scales little longer 6. S. vdlidus. 



Akenes 2.5 to 3 mm. long, the scales one-fourth longer. 7. S. ocddenlcdis. 

 Stems three-angled. 



Involucral leaf solitary S. S. americanus. 



Involucral leaves several. 



Spikelets 1 to 2 cm. long. 



Akenes oblong-obovate, pale 9. 8. hrittonianv^. 



Akenes orbicular-obovate, dark 10. S. robustus. 



Spikelets 3 to 5 mm. long. 



Akenes 3-angled; bristles 6 l\. S. atrovirens. 



Akenes plano-convex ; bristles 4 12. <S. microcarpus. 



1. Scirpus riparius (R. Br.) Spreng. Syst. 1: 208. 1825. 

 Isolepis riparia R. Br. Prod. Fl. Nov. Hoi. 222. 1810. 

 Type locality:- Port Jackson, Australia. 



Range: Washington to California. South America. Australia. Africa. 

 Specimens examined: Whidby Island, Gardner 318; Seattle, Piper 2860. 

 Zonal distribution: Humid Transition. 



2. Scirpus cespitosus L. Sp. PI. 1: 48. 1753. 

 Type locality: Europe. 



Range: Alaska to Greenland, south to Washington, Colorado, and New York. 

 Specimens examined: Olympic Mountains, Piper 2248; Skamania County, Suksdorf 



2241 ; Cascade Mountains, 49°, LyaU in 1860; Stevens Pass, Sandberg <& Leiberg775; Bridge 

 Creek, Elmer 644; Granville, Conard 376. 

 Zonal distribution: Arctic. 



