FLOWERING PLANTS AXD FERNS OF ARIZONA 399 



15. Basal leaves noticeably pinnate, the rachis 10 to 50 mm. long; 

 leaflets densely silvery-sericeous and often white-tomentose 



beneath 15. P. hippiaxa. 



1 2. Basal leaves digitate or nearly so, the rachis if any very short; leaflets 

 7 (rarely 9) or fewer (16). 

 16. Plants caulescent, the flowering stems erect or ascending, seldom 

 less and usually more than 20 cm. long; inflorescence several- 

 visual! v more than 5-) to many-flowered; petals 6 to 10 mm. long 

 (17). 

 17. Leaves sparsely villous with subappressed hairs, or glabrate, 

 light or yellowish green on both faces; leaflets merely coarsely 

 toothed 16. P. diversifolia. 



17. Leaves sericeous on both faces, copiously so beneath, dark green 



above, white or whitish on the lower face; leaflets cleft 

 nearly to the midvein into linear divisions. 



17. P. PECTIXISECTA. 



16. Plants subacaulescent, strongly cespitose, the flowering stems 

 spreading or prostrate, less than 20 cm. long; inflorescence few- 

 ( usually not more than 5-) flowered (18). 



18. Leaves more or less white-tomentose as well as sericeous beneath, 



green and sericeous above; styles rather short and thick. 



18. P. COXCIXXA. 



18. Leaves not white-tomentose beneath; styles elongate, filiform ( 1 9). 

 19. Plant conspicuously and densely silky- villous, obscurely if at 



all glandular 19. P. wheeleri. 



19. Plants sparsely villous or subhirsute, often also glandular- 

 puberulent, especially in the inflorescence (20) . 

 20. Leaflets of the basal leaves 5 (occasionally 7) ; inflorescence 

 usually with numerous tack-shaped glandular hairs. 



20. P. SUBVISCOSA. 



20. Leaflets of the basal leaves 3 ; inflorescence viscid but without 

 tack-shaped hairs 21. P. albiflora. 



1. Potentilla fruticosa L., Sp. PL 495. 1753. 



Dasiphora Jruticosa Rydb., Columbia Col. Bot. Mem. 2: 188. 

 1898. 



San Francisco Peaks and vicinity of Flagstaff (Coconino County), 

 White Mountains (Apache County), 7,000 to 9,500 feet, along streams 

 and in wet meadows, June to August. Widely distributed in the 

 cooler parts of the Northern Hemisphere. 



The only shrubby species in Arizona, browsed by sheep, goats, and 

 deer, sometimes until the plants are stunted. Rated as an excel- 

 lent erosion control species in localities to which it is adapted. Very 

 handsome when flowering. 



2. Potentilla arguta Pursh, Fl. Amer. Sept. 736. 1814. 



Potentilla conrallaria Rydb., Torr. Bot. Club Bui. 24: 249. 1897. 

 Drymocallis agrimonioides Rvdb., North Amer. FL 22: 368. 



1908. 

 Drymocallis conrallaria Rvdb., Columbia Col. Bot. Mem. 2: 



193. 1898. 



White Mountains, Apache County, on the White River (Hough in 

 1918) and on Bonito Creek, in meadows (Goodding 1219), Clear Creek 

 Canyon, Navajo County (Goodding 6473), June and July. New 

 Brunswick to Mackenzie, south to the District of Columbia, New 

 Mexico, and eastern Arizona. 



Hough's specimen is glabrate, Goodding's is more pubescent. 



L>si;744 — 412 26 



