1024 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 

 133. PINAROPAPPUS 



Low perennial herb, sometimes seapose; leaves entire to runcinate- 

 pinnatifid; heads solitary; receptacle bearing thin narrow paleae; 

 achenes subfusiform, tapering into a short beak; pappus of copious, 

 brownish, capillary bristles. 



1. Pinaropappus roseus Less., Syn. Gen. Compos. 143. 1832. 



Achyrophorus roseus Less., Linnaea 5: 133. 1830. 



Chiricahua and Huachuca Mountains (Cochise County), about 

 8,000 feet, open grassy pine forests, July to October. Louisiana 

 (where doubtless mtroduced), Texas, and Arizona, south to Guate- 

 mala. 



The large heads are white, turning pink in drying. 



134. MALACOTHRIX 



Annual herbs; leaves toothed to pinnatisect ; heads small or medium- 

 sized, yellow or white; involucre of subequal phyllaries and calyculate, 

 or strongly graduated, the phyllaries narrowly or broadly scarious- 

 margined; "achenes columnar, truncate, ribbed; pappus of soft bristles 

 deciduous more or less in a ring, 1 to 8 of them (rarely none) stiffer 

 and persistent, the achene often also crowned with a ring of minute 

 teeth. 



Key to the species 



1. Involucre 12 to 15 mm. high, strongly graduated, the phyllaries 3 to 4 mm. 

 wide, with a linear green and purplish midline and a very broad scarious 

 margin, all but the inner phyllaries suborbicular to oval; stem leaves 

 oblong or elliptic to ovate, cordate-clasping, the upper leaves subentire 



to repand-dentate, rarely laciniate 1. M. coulteri. 



1. Involucre 5 to 12 mm. high, calyculate but scarcely graduated, the phyllaries 

 1.5 mm. wide or less, lanceolate to linear, acute or acuminate, with a 

 narrow subscarious margin; leaves linear to oblong or ovate, mostly 

 pinnatifid (2). 



2. Leaf segments linear-filiform, less than 1 mm. wide 2. M. glabrata. 



2. Leaf segments oblong or triangular to linear-lanceolate, comparatively 



short, usually toothed (3) . 



3. Ligules inconspicuous, little exceeding the involucre; heads numerous, 



panicled, small (the involucre 5 to 8 mm. high) ; achenes finely 15- 



ribbed, with 1 (rarely 2) persistent pappus bristles and a crown of 



minute white setulose teeth 3. M. clevelandi. 



3. Ligules conspicuous, bright yellow, much exceeding the involucre; heads 

 larger, mostly solitary or few at the tips of the branches and branch- 

 lets ; pappus otherwise (4) . 

 4. Achene cylindric, evenly 15-ribbed, 2 mm. long, the outer coat prolonged 

 into a dark, truncate, unribbed, entire collar, this bearing inside 

 below the apex a denticulate whitish ring and to 2 persistent 



pappus bristles 4. M. fendleri. 



4. Achene more or less 5-angled (5 of the 15 ribs stronger than the others, 



sometimes almost winglike, continuous to the apex of the achene 



or prolonged beyond it into knoblike teeth), the outer coat not 



prolonged into a collar (5). 



5. Persistent bristles of the pappus 2 to 8, with minute teeth between 



them; 5 of the ribs of the achene much stronger than the others, 



almost winglike; phyllaries long-acuminate; achene 3 to 3.5 mm. 



long 5. M. TORREYI. 



5. Persistent bristles of the pappus none, the achene with a finely dentic- 

 ulate whitish crown; stronger ribs of the achene not winglike; 

 phyllaries merely acute or short-acuminate; achene about 2.5 

 mm. long L___ . 6. M. sonchoides. 



