60 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
19. CHAETOCHLOA Scribn. 
Annuals or perennials with flat leaves and bristly spikelike panicles; spikelets 
hermaphrodite, 1-flowered, or sometimes with a staminate flower below the hermaphro- 
dite terminal one, surrounded by few or many persistent awnlike branches springing 
from the pedicels below the articulation of the spikelets; glumes awnless; stamens 3; 
styles distinct; grain included within the hardened lemma end palea, free. 
KEY TO THE SPECIES. 
Panicles dense and thick. 
Spikelets arranged singly in racemes; 5 to 16 bristles at the base 
of each spikelet............0.0.0 0.0. c eee eee eee eee Leese 1. C. glauca. 
Spikelets clustered but not in racemes; 1 to 3 bristles at base of 
each spikelet.............. 2.2.0.0 cece eee cece eee e eee 2. C. viridis. 
Panicles slender, interrupted. 
Leaf blades more than 5 mm. wide; spikes with distinct, some- 
what spreading branches below..................-.-.2.- 3. C. grisebachii 
amopla. 
Leaf blades less than 5 mm. wide; spikes not branched below, 
merely interrupted..........2.22..22.022202.002-000 200 4. C. composita. 
1. Chaetochloa glauca (L.) Scribn. U.S. Dept. Agr. Div. Agrost. Bull. 4:39. 1897. 
PIGEON GRASs. 
Panicum glaucum L. Sp. Pl. 56. 1753. 
Setaria glauca Beauv. Ess. Agrost. 51. 1812. 
TYPE Loca.ity: ‘‘Habitat in India.”’ 
Range: A native of the Old World, widely introduced into North America, in New 
Mexico still rare. 
New Mexico: Kingston; Mesilla Valley; Roswell. 
2. Chaetochloa viridis (L.) Scribn. U. 8. Dept. Agr. Div. Agrost. Bull. 4: 39. 1897. 
GREEN FOXTAIL. 
Panicum viride L. Sp. Pl. ed. 2. 83. 1762. 
Setaria viridis Beauv. Ess, Agrost. 51. 1812. 
TYPE Loca.ity: ‘‘Habitat in Europa australi.’’ 
RanGE: Native of Europe, widely introduced into North America; in New Mexico 
acommon weed in cultivated fields. 
New Mexico: Common in waste and cultivated ground in nearly every part of 
the State. 
3. Chaetochloa grisebachii ampla Scribn. & Merr. U. 8. Dept. Agr. Div. Agrost. 
Bull. 21: 36. 1900. 
Tyre LocaLity: Organ Mountains, New Mexico. Type collected by G. R. Vasey. 
RanaeE: New Mexico and Arizona to northern Mexico. 
New Mexico: Mangas Springs; Hillsboro; Rio Frisco; Burro Mountains; Organ 
Mountains; Tortugas Mountain. Damp canyons, in the Upper Sonoran Zone. 
4. Chaetochloa composita (H. B. K.) Scribn. U. 8. Dept. Agr. Div. Agrost. Bull. 
4: 39. 1897. 
Setaria composita H. B. K. Nov. Gen. & Sp. 1: 111. 1816. 
TYPE LocaLity: ‘‘Crescit regione calidissima prope Cumana et Bordones, in Nova 
Andalusia: item in ripa fluminis Magdalenae prope Guarumo et in sylvis Orinocen- 
sibus juxta Esmeralda.’’ 
RanGe: Colorado and Arizona to Texas and Mexico; also in South America. 
New Mexico: Cross L Ranch; Albuquerque; Chiz; Animas Creek; Mangas Springs; 
Lake Valley; Aden; Rincon; Burro Mountains; Mesilla Valley ; Guadalupe Mountains; 
Pecos Valley. River valleys and low hills, in the Lower and Upper Sonoran zones. 
