ROBINSON AND GREENMAN. — GENUS VERBESINA. 539 



§ 5. Pterophyton, Gray. Heads large or medium-sized, solitary 

 or very few (rather numerous in V. ovata), mostly terminal on long 

 peduncles. Rays present, yellow. Scales of the involucre narrower, 

 oblong (broadly so in V. Lindheimeri) to linear. Pappus-awns short 

 or obsolete, never longer than the breadth of the achene. Leaves 

 opposite (except sometimes the uppermost), oblong and sessile or often 

 rhombic-ovate upon cuneately winged petioles. — Proc. Am. Acad. xix. 

 12, & Syn. Fl. i. pt. 2, 287, in part. Fterophyton, Cass. Bull. Soc. 

 Philom. 1818, p. 76, in part. — Herbaceous perennials of the Gulf 

 States and Mexico. 



* Peduncles winged to the heads : leaves opposite, rhombic to deltoid. 



10. V. TETRAPTERA, Gray, Proc. Am. Acad. xix. 13 (1883). xictl- 

 nomeris tetraj)tera, DC. Prodr. v. 57.5 (1836) ; Hemsl. 1. c. 186 (excl. 

 syn. V. scahra) . Helianthus tetrajjterus, Ort. Dec. vi. 74 (1798). 

 Coreopsis alata, Cav. Ic. iii. 30, t. 260 (1794). — Mexico, San Luis 

 Potosi, Parry & Palmer, no. 473|-, Schaffner, no. 257 ; State of 

 Mexico, Bourgean, no. 604, Pringle^ no. 3151; Oaxaca, Conzatti & 

 Gonzalez^ nos. 399, 399% Coulter^ no. 370. 



* * Main axis broadly winged up into a compound 12-20-headed corymb : leaves 



alternate, oblong. 



11. V. PTEROCAULA [Moc. & Scss.], DC. Prodr. V. 616 (1836); 

 A. DC. Caiques des Dess. t. 597. V. ovata, Gray, 1. c. (1883). V. 

 tetraptera, Klatt, Leopoldina, xx. 94, not Gray. Coreo2}sls ovata, 

 Cav. 1. c. 41, t. 280 (1794). Actinomeris ovata, Nutt. Gen. ii. 181 

 (1818); Hemsl. 1. c. 185. — S. Mexico, Eeal del Monte, Coulter, no. 

 363, Elirenhevfj , no. 351 ; Mt. Orizaba, Seaton, no. 340. 



* * * Peduncles long and wingless: heads solitary or few: stem winged below 



(except in V. Schaffneri, var. exalata). 



-t- Leaves oblong, green on both sides, sessile. 

 ■w- Rays yellow : Mexican. 



12. V. Rosei. Erect herbaceous perennial, 3 to 6 dm. high, bright 

 green and appearing glabrous, but under a lens strigillose : stems (nar- 

 rowly or broadly winged up to the highest pair of leaves) 1 or more from 

 a small lignescent stock with tough fibrous roots: leaves (3 to 4 pairs) 

 opposite, oblong to oblong-lanceolate, acute or obtuse, serrulate, 5 to 9 cm. 

 long, 1.5 to 2.5 cm. broad: peduncles 1 to 2, slender, 1-3-headed ; bracts 

 linear; pedicels long and slender; heads medium-sized 1 to 1.2 cm. broad 

 exclusive of the rays ; involucral scales 1-2-seriate, herbaceous, linear- 



