FLOWERING PLANTS AND FERNS OF ARIZONA 971 



March to November. Western Texas to southern Utah and Nevada, 

 southeastern California, and northern Mexico. 



Not always readily distinguishable from B. mult <ir ad lata. 



83. PERITYLE 



Herbaceous or suffruticulose, not woolly ; leaves toothed or dissected, 

 the lower ones opposite; heads small, radiate, the rays white; achenes 

 strongly compressed, strongly ciliate on the margin, usually with a 

 narrow callous margin; pappus of 1 or 2 awns and a crown of squamel- 

 lae. 



Key to the species 



1. Plants annual, conspicuously stipitate-glandular above (2). 



2. Achenes without an evident callous margin 1. P. emoryi. 



2. Achenes with a conspicuous callous margin 2. P. microglossa. 



1. Plants perennial, many-stemmed, cinereous-puberulent above, not obviously 



glandular (3). 



3. Leaves triangular in outline, ternately lobed or dissected. 



5. P. COROXOPIFOLIA. 



3. Leaves ovate, merely toothed (4). 



4. Leaves not impressed-punctate beneath 3. P. spilaxthoides. 



4. Leaves strongly impressed-punctate beneath 4. P. ciliata. 



1. Perityle emoryi Torr. in Emory, Mil. Reconn. 142. 1848. 

 Mohave, southern Yavapai, Maricopa, Pinal, and Yuma Counties, 



up to 3.000 feet, common on rocky slopes and cliffs, February to Octo- 

 ber. Southwestern Arizona, southern California, and northwestern 

 Mexico. 



The typical form has a pappus of squamellae and a slender awn. 

 In var. nuda (Torr.) A. Gray the awn is wanting. 



2. Perityle microglossa Benth., Bot. Yoy. Sulph. 119. 1845. 



Perityle microglossa var. effusa A. Gray, Svn. Fl. I 2 : 322. 



1884. 

 Perityle effusa Rose, Contrib. U. S. Xatl. Herbarium 1: 104. 



1891. 



Apparently known, to occur in Arizona only in the Santa Catalina 

 Mountains (Pima Count}'), where the type of var. effusa was collected 

 (Pringle in 1882). Southwestern Texas, southern Arizona (and south- 

 ern California?). 



Perityle ylumigera Harv. and Gray, a species of Sonora and Sinaloa, has been 

 doubtfully recorded from Arizona on the basis of the not definitely localized 

 original collection by Coulter. It is distinguished from P. microglossa by its 

 single pappus awn, longer than the achene and plumose above (in P. microglossa 

 the pappus of 2 short awns). 



*3. Perityle spilanthoides (Schultz Bip.) Rvdb., North Amer. Fl. 

 35: 17. 1914. 



Galinsogeopsls spilanthoides Schultz Bip. in Seem., Bot. Vov. 



Herald 307. 1856. 

 Perityle mlcrocephala A. Gray, Amer. Acad. Arts and Sci. 



Proc. 21: 391. 1886. 



Reported as occurring in Arizona, known otherwise only from 

 northern Mexico. 



