1556 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM 



65. FLOURENSIA DC. Prodr. 5: 592. 1836. 

 Reference: Blake, Revision of the genus Flourensia, Contr. U. S. Nat. Herb. 

 20: 393-409. 1921. 



Resinous shrubs; leaves alternate; heads j'ellow, radiate or discoid; involucre 

 2 to 4-seriate, the phyllaries herbaceous or subherbaceous; rays neutral; achenes 

 more or less thickened; pappus of 2 awns and rarely a few squamellae. 

 Heads discoid. 

 Leaves entire. 



Leaves ovate to obovate, 2 to 6 cm. wide 1. P. laurifolia. 



Leaves 4 to 11.5 mm. wide. 



Leaves narrowly lanceolate, 4 to 7.5 mm. wide 2. F. retinophylla. 



Leaves ovate to oval, 6.5 to 11.5 mm. wide 3. F. cernua. 



Leaves mucronate-dentate 4. F. ilicifolia. 



Heads radiate. 



Young branches densely pilose-lanate; heads numerous, in regular cymose 



panicles 5. F. glutinosa. 



Young branches not pilose-lanate; heads solitary to several at tips of branches, 

 not regularl.y cymose-panicled. 

 Petioles 7 to 15 mm. long; leaf blades ovate, 6 to 10 cm. long. 



6. F. coUodes. 

 Petioles 1 to 4 mm. long; leaf blades oblong to lanceolate, or if ovate only 

 1.5 to 2.5 v.m. long. 

 Phyllaries 13 to 23 mm. long, with ovate or lanceolate base and elongate 



linear-attenuate tips 7. F. pringlei. 



Phyllaries 7 to 15 mm. long, without linear-attenuate tips. 

 Leaf blades oblong-jUiplic to lanceolate, 3.3 to 6.5 cm. long. 



8. F. resinosa. 

 Leaf blades ovate or elliptic-ovate, 1.5 to 2.5 cm. long. 



9. F. microphylla. 



1. Flourensia laurifolia DC. Prodr. 5: 502. 1836. 



Helianthus laurifolius Benth. & Hook.; Hemsl. Biol. Centr. Amer. Bot. 2: 179. 

 1881. 



Tamaulipas and San Luis Potosi; type collected between Victoria and Tula, 

 Tamaulipas. 



Shrub 1.5 to 3 meters high; leaf blades 5.5 to 13 cm. long; heads in cymose 

 panicles of 3 to 7, the disk 1 to 1.3 cm. thick in flower. 



2. Flourensia retinophylla Blake in Robinson, Proc. Amer. Acad. 49: 505. 



1913. 

 Known only from the type locality, Sierra de la Paila, Coahuila. 

 Much-branched low viscid shrub; leaf blades 2.5 to 3.5 cm. long; heads 1 to 

 1.3 cm. high. 



3. Flourensia cernua DC. Prodr. 5: 593. 1836. 



Helianthus cernuus Benth. & Hook.; Hemsl. Biol. Centr. Amer. Bot. 2: 179. 

 1881. 



Sonora to Nuevo Le6n, south to Zacatecas and San Luis Potosi; type collected 

 between Monterrey and Lampasos, Nuevo Le6n. Texas to Arizona. 



Much-branched shrub 1 to 2 meters high, erect or procumbent; leaf blades 1.7 

 to 2.5 cm. long; heads nodding, solitary in the leaf axils, forming long leafy 

 inflorescences. "Hojase," "hojasen." 



This shrub has a hoplike odor and a bitter taste. The leaves and heads are 

 commonly sold in the markets of northern Mexico, and are taken as a remidy 

 for indigestion. According to Palmer, it is employed also as a remedy for female 

 diseases. In the United States the plant is known most commonly as "tar-bush. ; 



