204 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



New Mexico: Mesilla Valley; Alamillo; Albuquerque. Lower Sonoran Zone. 



A common tumbleweed in the southern part of the State. Without the fruit, 

 which appears rather late in the season, it may be confused with certain species of 

 Chenopodium. Herbarium specimens are easily confused with A. argentea, but 

 that is a smaller, whiter plant, with prevailingly petioled leaves. 



8. Atriplex argentea Nutt. Gen. PI. 1: 198. 1818. 



Type locality: "On sterile and saline places near the Missouri." 

 Range: British Columbia and North Dakota to New Mexico. 



New Mexico: Carrizo Mountains; Farmington; Rio San Jose. Plains and valleys, 

 in the Upper Sonoran Zone. 



9. Atriplex caput-medusae Eastw. Proc. Calif. Acad. II. 6: 316. 1896. 



Type locality: Not stated, but probably in southeastern Utah along the San Juan 

 River. 

 Range: Southern Utah and Colorado to northwestern New Mexico. 

 New Mexico: San Juan Valley. Dry hills, in the Upper Sonoran Zone. 



10. Atriplex semibaecata R. Br. Prodr. Fl. Nov. Holl. 406. 1810. 

 Atriplex flagellaris Woot. & Standi. Contr. U. S. Nat. Herb. 16: 119. 1913. 

 Type locality: Tasmania. 



Range: Australia and Tasmania; adventive from New Mexico to southern 

 California. 



New Mexico: Mesilla Valley; Alamorgordo. Dry fields, in the Lower Sonoran 

 Zone. 



11. Atriplex canescens (Pursh) Nutt. Gen. PI. 1: 197. 1818. Shad scale. 

 Calligonum canescens Pursh, Fl. Amer. Sept. 370. 1814. 



Obione canescens angustifolia Torr. U. S. & Mex. Bound. Bot. 121. 1859. 



Atriplex canescens angustifolia S. Wats. Proc. Amer. Acad. 9: 120. 1874. 



Atriplex angustior Cockerell, Proc. Davenport Acad. 9: 7. 1902. 



Type locality: "In the plains of the Missouri, near the Big-bend." 



Range: North Dakota to Arizona and northern Mexico. 



New Mexico: Common nearly throughout the State. Dry plains, in the Lower 

 and Upper Sonoran zones. 



This is one of the commonest shrubs over the plains, in arroyos, and in the lower 

 valleys of the Sonoran zones throughout the State. It is variously called "chamiso," 

 "chamis," and "sagebrush," the last name being used mostly by newcomers who 

 think that name applies to any grayish shrub. There are two forms common in the 

 southern part of the State. One of them is a plant about 100 to 150 cm. high with 

 short obovate or elliptic leaves, flowering generally in June and fruiting in late August 

 and September. The other is a taller plant, frequently 2 meters high or more, with 

 narrowly oblong-oblanceolate leaves, flowering and fruiting a month to 6 weeks earlier. 

 The latter is the form described as A. angustior by Professor Cockerell. This seems 

 also to be the form to which Dr. Rydberg applies the name tetraptera. 1 The same 

 writer maintains Atriplex occidentalis as a distinct species, but the characters depended 

 upon to separate it seem not to hold in New Mexican material. 



The plant is of considerable value as a forage plant wherever it grows, being 

 browsed extensively by cattle, sheep, and goats, particularly in winter and early 

 spring when other forage is scarce. It tolerates large quantities of alkali, but also 

 grows in soils where there is little or none, hence it is not always an indicator of alkali. 



12. Atriplex acanthocarpa (Torr.) S. Wats. Proc. Amer. Acad. 9: 117. 1874. 

 Obione acanthocarpa Torr. U. S. & Mex. Bound. Bot. 183. 1859. 



Type locality: Plains between the Burro Mountains, New Mexico. Type collected 

 by Bigelow. 



1 Bull. Torrey Club 39: 311. 1912. 



