8 PROCEEDINGS OF THE AMERICAN ACADEMY. 
species, but agreeing with the type in all floral characters except the 
somewhat broader involucral scales. 
= = Annuals. 
12. T. obovata, Turcz. Low, 4 to 6 inches in height: leaves 
obovate, subentire, obtuse: ligules short, yellowish. — Bull. Soc. Nat. 
Mose. xxiv. 187; Walp. Ann. 238.—S, Mexico, on Sierra San Pedro, 
Nolasco, Talea, &c., Jurgensen, no. 124. Here we would refer speci- 
mens collected near Acapulco by Palmer, no. 165. 7 
13. T. erecta, Gray. Slender, erect, hirsutulous, branching, 4 
foot or so in height: leaves ovate-lanceolate and serrate or broadly ovate — 
in outline and rather deeply 3-parted with acutish lobes: heads rather 
small: involucre ovate; one or two of the outer scales often narrow, 
oblong, and spreading: ligules short, only a line or two in length, 3- 
toothed, yellow. — Proc. Am. Acad. xxi. 390, 433. — Southwestern 
Chihuahua, Palmer, no, 285. 
T. tenuifolia, Rose. Erect, pubescent, 1 to 2 feet high, branch- 
ing: leaves ovate, petiolate, dentate but not lobed: outer scales of the 
involucre acuminate: rays conspicuous, 3 to 5 lines long, pale yellow oF 
“ bright white.” — Contrib. U. S. Nat. Herb. iii. 319. 7. bicolor, Gray; 
Proc. Am. Acad. xxi. 391, as to pl. Palmer. — Southwestern Chihuahua, 
on mountain sides above Batopilas, Palmer, no. 130. 
Var. microcephala, Rose, 1.c. Déscribed as differing in its smaller 
heads and “slightly different disk corollas.” —“ Near Lodiego, Palmer, 
no. 1611.” 
++ ++ Pappus shorter than the achenes. 
= Annual species of Northwestern Mexico: heads large, an inch in diameter. 
_> 15. T. bicolor, Gray. Erect annual, with leaves ovate to rather 
- narrowly oblong-lanceolate, serrate-dentate, not lobed, narrowed to slender 
petioles: ligules reddish or purplish, cuneate-oblong, 3-toothed. — Pi. 
Fendl. 104.— Llanos in the Sierra Madre, W. Chihuahua, Wislizenws: 
no. 214; also among rocks, Bachimba, Thurber, no. 833, and on rocky 
hills near the town of Chihuahua, Pringle, no. 638. 
= = Species of Southern Mexico, lignescent at the base. 
16. T. Galeottii, Klatt. “Stem terete, branched, pilose: mare 
petiolate, cuneate, irregularly lobed, pilose upon both surfaces, 2 inches 
long, 1} inches broad, 3-nerved: heads solitary, terminal ; involucral 
scales biseriate, the outer shorter: chaff 3—5-dentate at the apex. 
Leopoldina, xxiii. 6. Ptilostephium Galeotti, Schz. Bip. fide Klatt, 1. 
— Between San Andres and San Miguel, Liebmann, nos. 588, 693: and 
