FLOWERING PLANTS AND FERNS OF ARIZONA 981 



Columbia to northern New Mexico, northern Arizona, and California. 



Chaenactis gillespiei Stockwell (ibid. p. 123), described from a single collection 

 from near Granite Reef Dam, Maricopa County (Gillespie 5611), is insufficiently 

 known. It is an annual with bipinnatifid leaves with comparatively few, linear 

 segments, white flowers, and a double pappus of 4 long lanceolate inner paleae 

 and 1 to 4 short outer squamellae. 



95. CHAMAECHAENACTIS 



Dwarf scapose cespitose perennial; leaves small, roundish, crenate 

 or entire, slender-petioled, greenish above, canescent-strigose beneath. 

 3-nerved; heads medium-sized, discoid, flesh-colored, solitary on short 

 scapes; achenes slender, obpyramidal, about 5-ribbed, villous; pappus 

 of about 8 unequal, blunt, oblong, scarious paleae, these with a thick- 

 ened midrib. 



1. Chamaechaenactis scaposa (Eastw.) Rvdb., Torrey Bot. Club Bui. 

 33: 156. 1906. 



Chaenactis scaposa Eastw., Zoe 2: 331. 1891. 

 Fifteen miles north of Ganado, Apache County, 6,200 feet, May and 

 June (Peebles and Smith 13468). Southwestern Wyoming, south- 

 western Colorado, eastern Utah, and northeastern Arizona. 



96. BAHIA 



Herbs, rarely suffrutescent ; leaves opposite or alternate, entire to 

 dissected; heads radiate or rarely discoid, yellow; achenes narrow, 

 4-angled; pappus of several squamellae or paleae, these with a callous- 

 thickened base or midrib, or rarely wanting. 



Key to the species 

 1. Leaves oblong or elliptic, entire, green at maturity, about 1 cm. wide. 



1. B. OBLOXGIFOLIA. 



1. Leaves dissected or lobed or, if entire, then much narrower or else whitened 

 beneath (2). 

 2. Pappus wanting; plant normally 30 cm. high or more, glandular, especially 

 above; leaves once to thrice ternately divided into linear to oblong lobes; 



heads usually numerous and panicled 2. B. dissecta. 



2. Pappus present (3) . 



3. Heads discoid; low annual; leaves entire or 3-cleft, narrowly linear or 



linear-filiform 3. B. xeomexicaxa. 



3. Heads radiate (4). 



4. Stem glandular above (5) . 



5. Leaves pedately divided into 3 stipitate, mostly obovate or cuneate 

 divisions, these again lobed or parted, the ultimate divisions 

 broad; squamellae of the pappus in all the flowers very blunt, 

 with the nerve disappearing below the apex 4. B. pedata. 



5. Leaves biternately divided into linear segments about 1 mm. wide or 



less; squamellae of the pappus in the inner flowers pointed by the 



excurrent nerve 5. B. biterxata. 



4. Stem strigillose above, not evidently glandular (6). 



6. Heads solitary or few at the tips of the stem and branches, long- 



peduncled; achenes conspicuously long-hairy at base; leaves with 

 usually broad segments, sometimes entire; plants usually rela- 

 tively tall, canescent-puberulent with appressed hairs. 



8. B. ABSIXTHIFOLIA. 



6. Heads usually several (sometimes solitary) at the tips of the stem and 

 branches, on peduncles not more than 2 cm. long: achenes not 

 conspicuously long-hairy at base; leaves nearly all opposite, 3- or 

 5-parted into linear usually entire divisions, these 2.5 mm. wide 

 or narrower; plants low, much branched, not more than 20 cm. 

 high, green or merely cinereous (7). 



