552 PROCEEDINGS OF THE AMERICAN ACADEMY. 



heads 1 to 1.5 cm. in diameter, subglobose, very short-pedicelled in a 

 loose leafy corymb ; pedicels canesceut-tomentose ; scales of the involu- 

 cre herbaceous, suborbicular, obtuse or rounded at the apex, tomentulose : 

 ligules about 10, bright yellow, oblong, little exserted : achenes of the 

 disk-flowers oblanceolate, attenuate below, narrowly winged, 6 mm. long, 

 tipped with 2 (to 3) short subequal awns. — Atlixco, Puebla, Mexico, 

 E. W. Nelson, 25 July to 1 August, 1893, without number. Type in 

 herb. Gray and herb. U. S. Nat. Museum. 



* * » Leaves (silky-tomentose beneath) not decurrent, but stem with herbaceous 



wings. 



Gl. V. MOLLIS, HBK. Nov. Gen. & Spec. iv. 203; DC. Prodr. v. 

 617 ; Hemsl. 1. c. 188 ; Klatt, 1. c. xx. 94 (where identity of V. sericea 

 is suggested). V. sericea, Kunth & Bouche, Ind. Sera. Hort. Berol. 

 1848, 14; Walp. Ann. ii. 867; Hemsh 1. c. 190. — S. Mexico, origi- 

 nally coll. between Guanajuato and Villalpando by Humboldt & Bon- 

 2)land, mountains of Oaxaca, Galeotti, no. 2002, Pringle, no. 4863, 

 E. W. Kelson, no. 1782, CoJizatti & Gonzalez, no. 400. 



* * * * Leaves tomentulose beneath, bearing at the base of the short petiole one 



or two small thickish auricles which soon become corky and fall off: stem 

 ^ wingless : tips of the pales straight. 



62. V. ONCOPHpRA, Robinson & Seaton, Proc. Am. Acad, xxviii. 

 109. V. virgata, var. ? conyzoides, DC. Prodr. v. 616; A. DC. Caiques 

 des Dess. t. 596. V. conyzoides, [Moc. &. Sess. ace. to] DC. 1. c. 

 (1837), not Trew (1769). — State of Mexico, Bourgeau, no. 967, Prin- 

 gle, no. 4310. 



***** Leaves smoothish beneath : stem usually provided with narrow soon 

 corky wings or ridges more or less decurrent from the short petioles : tips of 

 the pales recurved. 



63. V. VIRGATA, Cav. Shrub 1 to 3 m. high. — Ic. iii. 38, t. 275. 

 V. salieifolia, HBK. 1. c. 205, although described as herbaceous, is with 

 scarcely a doubt a synonym, as suggested by Hemsl. Biol. Cent.- Am. 

 Bot. ii. 190. V. persicifolia, Klatt, Leopoldina, xx. 93, not DC. — 

 Valley of Mexico, Bourgeau, no. 963, Schmitz, no. 52, Schaffner, no. 6; 

 mountains of Oaxaca, Pringle, no. 4946, E. W. Nelson, no. 1380, Con- 

 zatti, no. 714; near Plateado, Zacatecas, Rose, no. 2753. 



****** Leaves not auricled at the base : stem not winged. 

 +- Leaves opposite, coarsely dentate. 



64. V. s ERRATA, Cav. Leaves ovate, finely pubescent above, cinere- 

 ous-pubescent beneath : pales shorter than or not greatly exceeding the 



