FLOWERING PLANTS AND FERNS OF ARIZONA 345 



9. STREPTANTHUS 



Plants annual or biennial, glabrous, glaucous; leaves entire to Jyrate- 

 pinnatifid; stem leaves clasping, with a cordate or sagittate base; 

 inflorescence racemose or paniculate; calyx flask-shaped, closed or 

 nearly so at anthesis, oehroleucous, yellow, or brown purple; petals 

 with long claws and narrow, crisped or channeled blades, these 

 brown purple, at least the veins; pods strongly compressed; seeds 

 flat, winged. 



Key to the species 



1. Stems slender, diffusely branched above; inflorescence an open panicle, brac- 

 teate, the bracts ovate or suborbicular; flowers not more than 8 mm. long; 

 pods about 1 mm. wide, 5 to 7.5 cm. long, becoming reflexed or pendu- 

 lous 1. S. LEMMONI. 



1. Stems stout, simple or few-branched; inflorescence racemose, elongate, ebrac- 



teate; flowers 10 mm. long or longer; pods 3 mm. wide or wider, erect or 



ascending (2). 



2. Leaves thick, the upper ones broadly ovate, obtuse or acutish, entire, the 



basal ones rather sharply dentate; calyx brown purple; plant very 



glaucous 2. S. CORDATUS. 



2. Leaves thin, the upper ones lanceolate, oblona, or ovate-lanceolate, acute 

 or acuminate, the basal ones commonly lyrate-pinnatifkl; calyx whitish 

 or yellow; plant moderately glaucous 3. S. arizoxicus. 



1. Streptanthus lemmoni S. Wats., Amer. Acad. Arts and Sci. Proc. 



25: 125. 1890. 

 Known only from the type collection, Santa Catalina Mountains, 

 Pima Count}', 5,000 feet (Lemmon 27). 



2. Streptanthus cordatus Xutt. ex Torr. and Gray, Fl. North Amer. 1: 



77. 1838. 



Streptanthus crassifolhis Greene, Pittonia 3: 227. 1897. 

 Euklisia crassifolia Evdb., Torrev Bot. Club Bui. 33: 142. 



1906. 



Navajo, Coconino, and Mohave Counties, 4,000 to 6,500 feet, April 

 to May. Wyoming to Oregon, New Mexico, northern Arizona, and 



California. 



3. Streptanthus arizonicus S. Wats., Amer. Acad. Arts and Sci. Proc. 



25: 125. 1890. 



Greenlee County to Pinal County, south to Cochise and Pima 

 Counties, 1,500 to 4,500 feet, January to April, type from mountains 

 of southern Arizona (Pringle in 1881). Arizona and Chihuahua. 



The calyx is normally oehroleucous. A form with bright-yellow 

 calyx, differing also in having a longer style and pods more attenuate 

 at apex, var. luteus Kearney and Peebles, occurs among rocks in 

 Canyon Diablo, Ajo Mountains, Pima County (Kearney 10813). 



10. LEPIDIFM. 47 Peppergrass 



Plants annual or perennial herbaceous or suffrutescent; stems 

 usually much branched; leaves pinnatifid to entire; flowers mostly 

 very small, in dense racemes, these becoming elongate and open in 

 fruit; pods 2-celled, dehiscent, orbicular or elliptic, often emarginate, 



47 Reference: Hitchcock, C. L. the gexus lepidium ix the united states. Madrono 3: 265-320, 

 1936. 



