490 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



nino County, far north of the range of A. bigelovii {MacDougal 439), 

 has the pods 2-celled to the apex. 



*72. Astragalus matthewsii S. Wats., Amer. Acad. Arts and Sci. Proc. 

 18: 192. 1883. 



Not known definitely to occur in Arizona, but the type was collected 

 at Fort Wingate, New Mexico, about 30 miles east of the Arizona 

 State line. 



Resembles the 2 preceding very hairy, acaulescent species, but the 

 pubescence is more appressed. 



73. Astragalus dispermus A. Gray, Amer. Acad. Arts and Sci. Proc. 



13: 365. 1878. 



Hesperastragalus dispermus Heller, Muhlenbergia 1 : 137. 1906. 



Pinal, Maricopa, and Pima Counties, 1,300 to 2,500 feet, February 

 to April, type from Wickenburg, Maricopa County. Southern 

 Arizona, southeastern California, and Baja California. 



An inconspicuous plant, differentiated from all of Arizona's other 

 species by the hard and sharp transverse ridges of the small pods. 



40. OXYTROPIS 



Plants perennial, herbaceous, acaulescent; leaves all basal, pinnate, 

 the leaflets numerous; racemes spikelike, elongate or subcapitate; 

 flowers white or purple, the keel w^ith a prominent erect or ascending 

 beak; pods indehiscent, ovate or oblong in outline, 1-celled or 

 imperfectly 2-celled. 



These plants resemble some of the acaulescent species of Astragalus. 

 The genus is a very weak one. 



Key to the species 



1. Leaflets fewer than 12, less than 1 cm. long, obtuse or acutish; inflorescence 

 subcapitate, not more than 2 cm. long, 3- to 8-flowered; peduncles not more 

 than 10 cm. long, ascending-spreading to (exceptionally) erect; corolla 10 

 to 12 mm. long 1. O. oreophila. 



1. Leaflets more than 12, more than 1 cm. long, very acute; inflorescence elongate, 

 many-flowered; peduncles seldom less than 12 cm. long, erect; corolla 15 

 to 20 mm. long, purple or whitish 2. O. lambertii. 



1. Oxytropis oreophila A. Gray, Amer. Acad. Arts and Sci. Proc. 20: 



3. 1884-5. 



Astragalus munzii L. C. Wheeler, Leaflets West. Bot. 2 : 209. 

 1939. 



Kaibab Plateau, Coconino County (Mead 664, Goodding 2454, 

 Goodman and Hitchcock 1626), about 8,000 feet, open meadows, July. 

 Idaho to California, Utah, and northern Arizona. 



None of the Arizona specimens has fruit, but they seem to represent 

 a rather luxuriant form of this species, which usually occurs at higher 

 altitudes. 



2. Oxytropis lambertii Pursh, Fl. Amer. Sept. 740. 1814. 



Oxytropis sericea Nutt. ex Torr. and Gray, Fl. North Amer. 1: 



339. 1838. 

 Aragallus knowltoni Greene, Biol. Soc. Wash. Proc. 18: 12. 



1905. 



Apache County to Coconino County and in the Chiricahua Moun- 

 tains (Cochise County), 5,000 to 7,500 feet, open sandy land and pine 



