STANDLEY TREES AND SHRUBS OF MEXICO 1637 



5. Gochnatia hypoleuca (DC.) A. Gray, Proc. Amer. Acad. 19: 57. 1883. 

 Moquinia hypoleuca DC. Prodr. 7: 23. 1838. 



Coahuila and Nuevo Le6n to Quer^taro; type from Monterrey, Nuevo Leon. 

 Texas. 



Shrub 2 to 2.5 meters high or "smaU tree," the stem cinereous- or canescent- 

 tomentose; leaves short-petioled or subsessile; heads 8 to 10 mm. high, 4 to 

 6-flowered, crowded toward tips of branches; involucre 5 to 6 mm. high, the 

 phyllaries obtuse to (inner) acute or obtusely acuminate. "Chomonque" 

 (Durango); "ocotiUo." 



6. Gochnatia obtusata Blake, Contr. U. S. Nat. Herb. 22: 652. 1924. 

 Puebla and Oaxaca; type from Tehuacdn, Puebla. 



Similar to G. hypoleuca; leaves smaller, obtuse or rounded; involucre longer 

 (6 to 8 mm.), the phyllaries acute or sharply acuminate. 



110. ONOSERIS Willd. Sp. PI. 3: 1480, 1702. 1804. 

 1. Onoseris rupestris (Benth.) Greenm. Proc. Amer. Acad. 41: 268. 1905. 



Caloseris rupestris Benth. PI. Hartw. 88. 1841. 



Rhodoseris conspicua Turcz. Bull. Soc. Nat. Moscou 24: 95. pi. 2. 1851. 



Pereziopsis donnell-smithii Coulter, Bot. Gaz. 20: 53. pi. 6. 1895. 



Onoseris conspicua Greenm. Proc. Amer. Acad. 41: 268. 1905. 



Michoaedn (or Guerrero) to Oaxaca and Chiapas. Guatemala; type from 

 Mount Chorro. 



"Shrub, 4 meters high," white-tomentose throughout, the upper surface of the 

 leaves usually and the involucre sometimes glabrate; leaves alternate, 25 to 40 

 cm. long (including petiole), lyrate-pinnatifid, the terminal lobe very large, 

 deltoid, usually hastate, coarsely dentate, the 2 or 3 lower pairs of lobes much 

 smaller, unequal, the rachis very narrowly winged; heads panicled, cylindric- 

 turbinate, 6 to 12-flowered, about 2.5 cm. high; involucre graduate, 2.3 to 2.5 

 cm. high, of linear or linear-lanceolate attenuate phyllaries; corollas crimson, all 

 bilabiate (4 and 1); pappus 2 cm. long, of numerous brownish white bristles; 

 anthers long-caudate at bast. "Papelillo." 



111. TRIXIS (P. Br. Civ. Nat. Hist. Jam. 312. 1756, hyponym); Crantz, 



Inst. Herb. 1: 329. 1766. 

 Reference: Robinson & Greenman, Revision of the Mexican and Central 

 American species of Trixis, Proc. Amer. Acad. 40: 6-14. 1904. 



Shrubs, rarely herbs; leaves alternate, entire or dentate; heads cymose or 

 panicled, yellow; involucre double, the outer phyllaries few, usually shorter, 

 linear to ovate, herbaceous, the inner 5 to 10, equal, subherbaceous; flowers all 

 hermaphrodite and fertile, the corollas all bilabiate, the outer lip 3-toothed, the 

 inner 2-cleft; achenes subcyhndric, papillose; pappus of numerous usually 

 brownish bristles; anthers caudate at base. 



The following names are reported for species of this genus whose identity is 

 uncertain: "Metatera" (Hidalgo); "manzanilla" (Sinaloa); "pichaguilla," 

 "pichaga." 

 Leaves decurrent. 



Leaves shortly decurrent 1- T. decurrens. 



Leaves long-decurrent, winging the stem. 



Outer phyllaries equaling or surpassing the inner. 



Outer phyllaries lance-ovate or oblong-lanceolate, acuminate-2. T. alata. 



Outer phyllaries elliptic, barely acute 3. T. calcicola. 



Outer phyllaries shorter than the inner. 



Outer phyllaries narrow, about one-third as long as the inner. 



4. T. mexicana. 



