WOOTON AND STANDLEY—FLORA OF NEW MEXICO, | 115 
Involucral bract 4 to 10 cm. long, much exceeding the 
spikelets, these few, frequently only 1; leaves 
half as long as the culm or more........ pe eeeee 3. S. americanus. 
Involucral bracts of several flat leaves much exceeding the com- 
pound umbellate inflorescence. 
Culms triangular; spikelets large, 10 to 30 mm. long, light yel- 
lowish brown; inflorescence a simple umbel or in young 
plants capitate . 2.2.0.2... 22. eee eee eee 4. S. brittonianus. 
Culms terete; spikelets small, 2 to 7 mm. long, greenish; inflo- 
rescence a once or twice compound umbellate cluster 
with numerous unequal rays. 
Style branches 2; achenes rounded on the back; inflores- 
cence twice compound; spikelets not capitate...... 6. S.microcarpus. 
Style branches 3; achenes angled on the back; inflores- 
cence generally once compound; spikelets densely 
capitate at the ends of the rays..............-..--. 7. S. atrovirens. 
1. Scirpus pauciflorus Lightf. Fl. Scot. 1078. 1777. 
Eleocharis pauciflorus Link, Hort. Berol. 1: 284. 1827. 
Type Locaity: Highlands of Scotland. 
Rance: British America to New York, New Mexico, and California; also in Europe. 
New Mexico: A single specimen without locality seen. 
It is probable that the plant is not uncommon in the mountains of New Mexico but 
has been overlooked by collectors. 
2. Scirpus olneyi A. Gray, Bost. Journ. Nat. Hist. 5: 238. 1845. 
TyPE LocaLity: In a salt marsh on the Seekonk River, Rhode Island. 
Rane@eE: Across the United States. 
New Mexico: Salt Lake; Santa Rita; Dog Spring; Round Mountain. Wet alkaline 
soil, in the Upper Sonoran Zone. 
3. Scirpus americanus Pers. Syn. Pl. 1: 68. 1805. 
Scirpus pungens Vahl, Enum. Pl. 2: 255. 1808. 
Type Loca.ity: ‘‘Hab. in Carolina inferiore.”’ 
Rance: Throughout North America; also in South America. 
New Mexico: Farmington; Carrizo Mountains; Taos; San Juan; Wheelers Ranch; 
Berendo Creek; Rincon; Mesilla Valley. In swamps, in the Lower and Upper Sonoran 
, zones. 
4. Scirpus brittonianus Piper, Contr. U. 8. Nat. Herb. 11: 157. 1906. 
Scirpus campestris Britton in Britt. & Brown, Illustr. Fl. 1: 267, 1896, not Roth, 
1800. 
Scirpus robustus campestris Fernald, Rhodora 2: 241. 1900. 
TYPE LOCALITY: ‘‘On wet prairies and plains, Manitoba and Minnesota to Nebraska, 
Kansas, and Mexico, west to Nevada.”’ 
RaNnGE: As under type locality. 
New Mexico: Carrizo Mountains; Farmington; Salt Lake; Mesilla Valley; near 
Carrizozo; Roswell. Wet ground, in the Lower and Upper Sonoran zones. 
5. Scirpus occidentalis (S. Wats.) Chase, Rhodora 6: 68. 1904. 
Scirpus lacustris occidentalis 8. Wats. Bot. Calif. 2: 218. 1880. 
TYPE LocaALity: San Diego County, California. 
RanGeE: British Columbia and California to New England. 
New Mexico: Shiprock; Farmington; Gallo Spring; Mangas Springs; Berendo 
Creek; Mesilla Valley; Roswell; Carrizozo. Wet ground, in the Lower aud Upper 
Sonoran zones. 
