52 ■ CONTEIBUTIONS FEOM THE NATIONAL HEKBAEIUM. 



1, Holcus halepensis L. Sp. PI. 1047. 1753, Johnson grass. 



Andropogon halepensis Bret. Fl. Lusit 1: 89. 1804. 



Sorghum halepense Pers. Syn. PI. 1: 101. 1805. 



Type locality: "Habitat in Syria, Mauritania." 



Range: Native of the Old World, widely introduced into North America, frequent 

 as a weed in cultivated fields. 



New Mexico: Nara Visa; Mangas Springs; Hillsboro; Gila; Deming; Mesilla 

 Valley; Pecos Valley. 



This is common in several parts of New Mexico, especially in the irrigated river 

 valleys. So far it has not been introduced into the valley of the San Juan, but it is 

 well established in those of the Rio Grande and Pecos. In some parts of the State it 

 has been cultivated for hay. Unfortunately it is a very troublesome weed, and in the 

 Rio Grande Valley has become a dangerous pest in alfalfa fields, taking possession of 

 them and crowding out the less aggressive alfalfa. 



8. SORGHASTRTJM Nash. Indian grass. 



Stout perennials with racemes arranged in open panicles; spikelets sessile at each 

 joint of the slender rachis of the peduncled racemes, these reduced to 2 or 3 joints; 

 sterile spikelets reduced to hairy pedicels; glumes indurated ; sterile lemma hyaline, 

 the fertile lemma reduced to hyaUne appendages to the stout awn; palea obsolete. 



1. Sorghastrum nutans (L.) Nash in Small, Fl. Southeast. U. S. 66. 1903. 



Andropogon nutans L. Sp. PI. 1045. 1753. 



Andropogon avenaceus Michx. Fl. Bor. Amer. 1: 58. 1803. 



SorgJium nutans A. Gray, Man. 617. 1848. 



Type locality: "Habitat in Virginia, Jamaica." 



Range: British America to Arizona and Florida. 



New Mexico: Tesuque; Las Vegas; Clayton; East View; Kingston; RioMimbres. 

 Plains, in the Upper Sonoran Zone. 



9. HETEROPOGON Pers. 



Coarse perennial with narrow leaves, compressed sheaths, and terminal solitary 

 dense racemes; spikelets 1-flowered, in pairs at the rachis nodes, one sessile and fertile, 

 the other pedicellate and staminate or sterile; glumes firm, convolute, awnless; lemma 

 small, hyaline, awned; palea small and hyaUne, or wanting; stamens 3; styles distinct. 



1. Heteropogon contortus (L.) Roem. & Schult. Syst. Veg. 2: 836. 1817. 



Andropogon contortus L. Sp. PI. 1045. 1753. 



Type locality: "Habitat in India." 



Range: Arizona and New Mexico to Tropical America; in tropical lands nearly 

 around the world. 



New Mexico: Hillsboro; Tortugas Mountain; Organ Mountains. Dry hills, in the 

 Lower and Upper Sonoran zones. 



10. NAZIA Adans. 



Diffusely branched annual 'ndth flat leaves and terminal spikelike inflorescence; 

 spikelets in groups of 3 to several at each joint of the main axis, the uppermost in 

 each fascicle sterile, 1-flowered; first glume minute or wanting; second glume rigid, 

 exceeding the lemma, its back covered with hooked spines; lemma and palea hya- 

 Une; stamens 3; styles short and distinct; grain oblong, free. 



1. Nazia aKena (Spreng.) Scribn. U. S. Dept. Agr. Div. Agrost. Bull. 17: 28. 1899. 

 Lappago aliena Spreng. Neu. Entd. 3: 15. 1822. 

 Tragus alienus Schult. Mant. 2: 205. 1824. 

 Type locality: "Hab. in Brasilia." 



