FLOWERING PLANTS AND FERNS OF ARIZONA 271 



Opuntia. Three forms, all intergrading, and similar in geographical 

 distribution, occur in Arizona. In var. fasdcvlata (S. Wats.) M. E. 

 Jones (A. fasdcvlata S. Wats.) the margins of the fruits commonly are 

 dissected only half way to the base, with relatively broad teeth, the 

 stems are decumbent or nearly prostrate, and the leaf blades are 

 obovate or broadly spatulate, commonly more than 6 mm. wide. 

 In typical A. elegans the margins of the fruits are dissected nearly or 

 quite to the base with slender teeth, the stems tend to be erect, and 

 the leaf blades are usually narrower. The var. thornberi M. E. Jones 

 differs from typical A. elegans only in having the faces of the bracts 

 prominently crested. 



8. Atriplex wrightii S. Wats.. Amer. Acad. Arts and Sci. Proc. 9: 113. 

 1874. 



Coconino County to Cochise and Pima Counties. 1,000 to 7,000 feet. 

 Southern New Mexico, Arizona, and Sonora. 



Common, especially in southern Arizona, in similar habitats as are 

 occupied by ^4. elegans. It is usually a larger plant than the latter. 

 This is one of the species held by the Indians in particular esteem as 

 a potherb. 



*9. Atriplex serenana A. Xels. in Abrams, Fl. Los Angeles 128. 1904. 



Obione bracteoza Dur. and Hilg.. U. S. Rpt. Expl. Miss. Pacif. 



5 3 : 13. 1858. 

 Atriplex bracteosa (Dur. and Hilg.) S. Wats., Amer. Acad. 



Arts and Sci. Proc. 9: 115. 1874. Not Trautv. 1870. 



Not known to occur in Arizona but has been collected at Needles, 

 Calif., on the Colorado River. 



10. Atriplex acanthocarpa (Torr.) S. Wats., Amer. Acad. Arts and Sci. 



Proc. 9: 117. 1874. 



Obione acanthocarpa Torr., U. S. and Mex. Bound. Bot. 183. 

 1859. 



Gila River Valley near Safford (Graham County), about 3,300 feet, 

 in saline soil. Western Texas to southern Arizona and northern 

 Mexico. 



The Arizona specimens referred doubtfully to this species have the 

 fruiting bracts less united and thinner and less spongy in texture than 

 in typical A acanthocarpa. Apparently they represent a transition 

 to A. obovata, with which they were growing. 



11. Atriplex obovata Moq., Chenop. Monog. 61. 1840. 



Atriplex greqgii S. Wats., Amer. Acad. Arts and Sci. Proc. 

 9: 118. 1874. 



Near Safford (Graham County), 2,600 to 3,300 feet. Western Texas 

 to southern Arizona and northern Mexico. 



12. Atriplex jonesii Standi., North Amer. Fl. 21: 65. 1916. 



Atriplex sabulosa M. E. Jones, Contrib. West. Bot. 11: 21. 

 1903. Not of Rouy, 1890. 



Apache County to eastern Coconino County, 3,500 to 5,000 feet, in 



dry saline soil. Northwestern New Mexico and northeastern Arizona. 



This species has been united with .1. obovata (see footnote 40, p. 267) . 



286744°— 42 18 



