STANDLEY TEEES AND SHRUBS OF MEXICO 1449 



A low, much-branched, nearly glabrous, calciphile shrub; leaves lanceolate to 

 narrowly ovate, attenuate, subentire, mostly rounded at base, 3 to 5.5 cm. long, 



1 to 1.8 cm. wide; petiole 4 to 10 mm. long; heads about 5-flowered, often closely 

 aggregated by 2's and 3's at the tips of the branchlets of the ovoid thyrselike 

 panicles; phyllaries about 8, lanceolate, 3-nerved; corollas white. 



32. Eupatorium collodes Robins. & Greenm. Amer. Journ. Sci. III. 50: 152. 

 1895. 



Oaxaca; type from Las Sedas. 



A subglabrous but somewhat viscid and vernicose shrub, 60 to 90 cm. high; 

 branches virgate, leafy, purple; leaves opposite, ovate, sessile, acute, serrate 

 except near the rounded base, 2 to 3.5 cm. long, 1.3 to 2 cm. wide, subcoriaceous; 

 heads 20 to 25-flowered, in round-topped corymbs (5 to 10 cm. in diameter) ; 

 phyllaries lance-linear, puberulent and ciliate, acute, usually purple; corollas 

 white; pappus rose-colored. 



33. Eupatorium bigelovii A. Gray in Torr. U. S. & Mex. Bound. Bot. 75. 

 1858-59. 



Eupatorium bigelowii Hemsl. Biol. Centr. Amer. Bot. 2: 93. 1881. 



Eupatorium madrense S. Wats. Proc. Amer. Acad. 26: 137. 1891. 



Coahuila, Nuevo Le6n, and San Luis Potosi. Type collected on the Gila in 

 Arizona. 



Shrub or slightly lignescent perennial herb; leaves ovate, acute, sharply and 

 often rather coarsely serrate, 3-nerved, rounded at base, 3 to 7 cm. long, 1.5 to 

 3.5 cm. wide, finely pubescent above, pubescent to canescent-tomentose beneath; 

 petioles mostly 2 to 7 mm. long; heads 1.2 to 1.6 cm. high, many-flowered, in 

 few-headed cymes; phyllaries lanceolate, acutish to acuminate, striate, green or 

 more often purple; corollas purplish. 



A calciphile of middle altitudes. 



34. Eupatorium. turbinatum A. Gray, Proc. Amer. Acad. 15: 26. 1880. 

 Known only from the original collection, secured in a mountain ravine between 



San Luis Potosf and Tampico. 



Probably somewhat shrubby; stems erect, subterete, purple, soon glabrate, 

 leafy; leaves opposite, sessile, ovate, attenuate, rounded at base, sharply serrate 



(the teeth few, subremote and unequal), 3-nerved, smooth or nearly so above, 

 softly pubescent to grayish-tomentose beneath, of firm texture, 5 to 6 cm. long, 



2 to 3 cm. wide; heads corymbed or subsolitary, pediceled, 30 to 40-flowered, 

 1.5 cm. long; involucre turbinate; phyllaries numerous, linear, subulate-attenuate, 

 striate, purplish, of firm texture. 



35. Eupatorium azureum DC. Prodr. 5: 168. 1836. 



Tamaulipas, Nuevo Le6n, and San Luis Potosi; type collected at Monterrey. 



Shrub with spreading tomentellous branches; stem leaves deltoid-ovate, 

 acute, nearly truncate or even subcordate at base, coarsely toothed at the broadest 

 part, somewhat puberulent above, pubescent to grayish-tomentellous beneath, 

 usually 4 to 6 cm. long, 3 to 4 cm. wide, on slender petioles (1 to 2 cm. long), the 

 rameal leaves usually smaller and more narrowly ovate; heads about 1 cm. in 

 diameter, usually 40 to 70-flowered, slender-pediceled, in small, rather dense, 

 terminal corymbs; phyllaries herbaceous, striate, at least the inner acute; 

 corollas azure. 



Used for astringent poultices (Gregg) . 



36. Eupatorium oresbiumi Robinson, Proc. Amer. Acad. 35: 337. 1900. 

 Morelos; type from a "wet mountain canyon above Cuernavaca, 6,500 ft." 

 Shrub, 3 to 5 meters high; leaves opposite, ovate, acuminate, cuspidate- 

 dentate, rounded or subcordate at base, 5 or 7-nerved near the base, thin, 

 spreading-villous on the nerves beneath, otherwise nearly smooth, about 13 cm. 



