26 NORTH AMERICAN FLORA [Volume 34 



lanceolate salient teeth, 1-2 cm. long, puberulent and somewhat punctate, triple-ribbed; 

 involucre turbinate, 5 mm. high, about 6 mm. broad; bracts oblanceolate, grayish-puberulent ; 

 rays wanting; disk-corollas fully 3 mm. long; tube slightly shorter than the deeply campanulate 

 throat; achenes fully 3 mm. long, pilose; pappus wanting. 



Type locality: Crevices of rocks along the Rio Grande, Texas. 

 Distribution: Western Texas. 



5. Laphamia angustifolia A. Gray, PI. Wright. 1: 100. 1852. 



A perennial with a thick woody caudex; stem about 1 dm. high, minutely and sparingly 

 puberulent; leaves alternate or some opposite; blades lanceolate or oblanceolate, with a few 

 sharp teeth or entire, 1-1.5 cm. long, glandular-punctate, less distinctly 3-ribbed; heads corym- 

 bose; involucre 4 mm. high, 4—5 mm. broad; bracts linear-oblanceolate, slightly puberulent, 

 ciliate towards the apex; rays wanting; disk-corollas 2.5 mm. long; tube nearly equaling the 

 narrowly campanulate throat; achenes oblong-oblanceolate, puberulent, 2 mm. long; pappus 

 wanting. 



Type locality: "Between Texas and El Paso." 

 Distribution: Western Texas. 



6. Laphamia bisetosa Torr.; A. Gray, PI. Wright. 2: 106. 1853. 



A dwarf perennial with a thick woody caudex; stems many, about 3 cm. high, scabrous- 

 hispidulous; leaves opposite and alternate, short-petioled ; blades about 5 mm. long, ovate or 

 obovate, thick, entire or with 1 or 2 teeth, glandular-punctate; heads subsessile; involucre 

 campanulate, 5 mm. high, 3 mm. broad; bracts 6-8, oblanceolate, ciliate at the apex; rays none; 

 disk-flowers 6-8; corolla 4 mm. long; tube half as long as the cylindric throat; achenes oblong, 

 puberulent; pappus of 2 awns, shorter than the achene. 



Type locality: Canon of the Rio Grande, below Presidio del Norte [on the label given as 

 below Mt. Carmel, Rio Grande]. 

 Distribution: Western Texas. 



16. PAPPOTHRIX (A. Gray) Rydberg, gen. nov. 



Laphamia § Pappothrix A. Gray, PI. Wright. 1: 99. 1852. 



Low suffruticose perennials with woody bases. Leaves opposite or alternate, petioled; 

 blades broad, 3-ribbed. Heads discoid, mostly solitary at the ends of leafy branches, short- 

 peduncled. Involucre campanulate; bracts few, linear or linear-oblanceolate, flat and rather 

 thin. Receptacle flat. Disk-flowers rather few; tube much shorter than the cylindric or 

 cylindro-funnelform throat. Achenes oblong, flat, not ciliate on the margins. Pappus of 

 15-30 barbellate subulate awns. 



Type species, Laphamia rupestris A. Gray. 



Leaves densely pubescent; involucre about 4 mm. broad. 



Plant arachnoid and viscid -pubescent. 1. P. rupestris. 



Plant finely and densely villous. 2. P. cinerea. 



Leaves nearly glabrous; involucre 8-10 mm. wide. 3. P. cernua. 



1 . Pappothrix rupestris (A. Gray) Rydberg. 



Laphamia rupestris A. Gray, PI. Wright. 1: 100. 1852. 



A perennial with thick woody caudex; stems diffuse, about 1 dm. high, subviscid-pubescent ; 



leaves opposite and alternate, petioled ; blades pubescent and glandular-granuliferous, rounded 



or deltoid, dentate to deeply laciniate, 1-1.5 crn. long; heads at the ends of short leafy branches; 



involucre cylindric, about 6 mm. high and 4 mm. broad; bracts oblong-oblanceolate, puberulent 



and ciliate; rays wanting; corollas of the disk-flowers ochroleucous (?); tube 1 mm. long; 



throat nearly cylindric, 3 mm. long; achenes narrowly oblong, hirsutulous, 2.5 mm. long, with 



thickened margins; pappus of about 20 subulate, barbellate awns. 



Type locality: Pass of the Limpia, Texas. 



Distribution: Western Texas. 



Illustration: A. Gray, PI. Wright. 1: pi. 9, A. 



