FLOWERING PLANTS AND FERNS OF ARIZONA 369 



very fine dense indument on the basal leaves and lower portions of the 

 plant. The species is abundant in the basin ranges to the north. 



8. Arabis perennans S. Wats., Amer. Acad. Arts and Sci. Proc. 22: 



467. 1887. 



Arabis eremophila Greene, Pittonia 4: 194. 1900. 

 Arabis graeilenta Greene, ibid. 

 Arabis recondita Greene, ibid., p. 195. 



Apache County to Mohave County, south to Graham and Pima 

 Counties, 2,000 to 5,000 feet, lower mountain slopes and hot canyons, 

 February to May, type from Santa Catalina Mountains (Pima 

 County), type of A. eremophila from Peach Springs (Mohave County), 

 type of A. recondita from Diamond Creek (Mohave County.) Western 

 Colorado to Arizona, southern California, northern Mexico, and Baja 

 California. 



Arabis perennans often develops a ligneous footlike extension of the 

 caudex between the functional basal leaves and the ground surface. 

 This foot appears to be formed as a result of the shedding of basal 

 leaves during successive seasons and the occurrence of new leaves at a 

 higher level on the caudex each succeeding year. Arabis perennans is 

 the earliest-flowering and most abundant species of the genus in 

 Arizona. 



9. Arabis fendleri (S. Wats.) Greene, Pittonia 3: 156. 1897. 



Arabis holboellii Hornem. var. fendleri S. Wats, in A. Gray, 

 Syn. Fl. 1: 164. 1897. 



Coconino and northern Mohave Counties, 5,000 to 8,000 feet, open 

 pine woods, April to June. Colorado and New Mexico to Nevada and 

 northern Arizona. 



Arabis fendleri is much like A. perennans in habit of growth, but the 

 latter flowers much earlier, and ordinarily occurs at lower altitudes. 



33. ERYSIMUM 



Plants annual, biennial, or perennial, rather coarse, with appressed 

 harsh pubescence; leaf blades entire or repand-dentate; petals 6 mm. 

 long or longer, yellow, orange or maroon; pods elongate, 4-sided, rigid, 

 erect to recurved-spreading, the valves strongly keeled; seeds in 1 row 

 in each cell. 



Key to the species 



1. Pods divaricate, often somewhat curved, about 1 mm. wide; petals not more 

 than 8 mm. long, pale yellow; leaf blades repand-dentate. 



1. E. REPAXDUM. 



1. Pods ascending; or erect, straight or nearly so, commonly more than 1 mm. 

 wide; petals more than 10 mm. long; leaf blades entire or sparingly dentate. 



2. E. CAPITATUM. 



1. Erysimum repandum L., Amoen. Acad. 3: 415. 1756. 



Cheirinia repanda Link, Enum. PI. 2: 171. 1S22. 



Flagstaff and Mormon Lake (Coconino County), Ash Fork (Yavapai 

 County), Gila River bed (Pinal County), April to June. Ohio to 

 Oregon and Arizona; introduced from Europe. 



