FLOWERING PLANTS AND FERNS OF ARIZONA 325 



4. Clematis hirsutissima Pursh, Fl. Amer. Sept. 385. 1814. 



Clematis douglasii Hook., Fl. Bor. Amer. 1: 1. 1829. 

 Viorna hirsutissima Heller, Muhlenbergia 1: 40. 1904. 



Coconino County, Kaibab Plateau (Jones 6056v), north rim of the 

 Grand Canyon (Tidestrom 2309. McHenry 2068, Collom in 1939), 

 about 8,000 feet. Montana to Washington, south to northern 

 Arizona. 



5. Clematis arizonica Heller, Torrey Bot. Club Bui. 26: 547. 1899. 



Viorna arizonica Heller, Muhlenbergia 1: 40. 1904. 



Coconino County. Grand Canyon and vicinity of Flagstaff. 7,000 to 

 8,000 feet, April to July, type from Walnut Canyon (MacDougal 343). 

 New Mexico and northern Arizona. 



Perhaps not specifically distinct from C. hirsutissima. 



6. Clematis bigelovii Torr., U. S. Rpt. Expl. Miss. Pacif. 4: 61. 1856. 



Viorna bigelovii Heller, Muhlenbergia 6: 96. 1910. 



Fort Apache, Navajo County (Mrs. R. W. Hoyt), also in the 

 Tunitcha Mountains. New Mexico, very near the Arizona State line. 

 New Mexico and eastern Arizona. 



7. Clematis palmeri Rose, Contrib. U. S. Xatl. Herbarium 1: 118. 



1891. 



Viorna palmeri Woot. and Standi.. Contrib. U. S. Xatl. 

 Herbarium 16: 123. 1913. 



Known in Arizona only from the type collection at Fort Apache, 

 Navajo County, 5,000 feet (Palmer 600), and from a collection at 

 Black River, White Mountains (Goodding 4417). Occurs also in 

 southwestern Xew Mexico. 



9. MYOSURUS. Mousetah, 



Plants annual, dwarf; leaves all basal, the blades narrowly linear or 

 oblanceolate, entire; flowers solitary on slender scapes, inconspicuous; 

 sepals commonly 5. deciduous; petals rudimentary or none; stamens 

 5 to numerous; pistils many; achenes in a dense, slender, cylindric 

 spike. 



Key to the species 



1. Achenes when mature roundish, with a dorsal cup or border nearly surrounding 



the base cf the beak, the cup often larger than the body of the achene (2). 



2. Border of the achene deep, cup-shaped, suborbicular, erose or nearly entire, 



corky-thickened, the beak stout, triangular, strongly flattened laterally; 



plant up to 15 cm. high 1. M. cupttlatus. 



2. Border of the achene shallow, relatively thin, the beak elongate, subulate; 



plant not more than 3 cm. high 2. M. egglestonii. 



1. Achenes when mature more or less quadrangular, without cup or border, keeled 

 dorsallv from base to apex, the beak subulate, not strongly flattened 

 laterally (3). 



3. Back of the achene scarcely wider on each side than the very prominent keel, 



the le* + er prolonged into a beak at least half a- l>>Mu r a- the body of the 



achene 3. M. aristatus. 



3. Back of the achene distinctly wider on each side than the relatively low keel, 

 the latter prolonged into a beak much less Than half a- loDg a- the body of 

 the achene, or the beak sometimes obsolete 1. M. minimus. 



