278 PROCEEDINGS OF THE AMERICAN ACADEMY 



somewhat ribbed on the face. — On cool slopes of the Sierra Madre, 

 Chihuahua; C. G. Pringle (n. 1305), Sept., 1887. 



Helianthella Madrensis. Root thick and fleshy : stems spar- 

 ingly pubescent or glabrate, nearly naked, 2 feet high, bearing 3 to 

 5 long-pedunculate flowers : leaves mostly radical, linear and long- 

 petiolate, acute or acuminate, 4 to 10 inches long (cauline much 

 shorter), entire, glabrous above, subscabrous- beneath : heads rather 

 small (5 or 6 lines high) ; involucre finely pubescent, the bracts 

 strongly 3-7-nerved : ray-flowers 9 lines long: chaff thin and sca- 

 rious : pappus, of 2 short slender awns and numerous dissected squa- 

 mulas. — On pine plains at the base of the Sierra Madre, Chihua- 

 hua; C. G. Pringle (n. 1302), September, 1887. Allied to H. Mexi- 

 cana. 



Bidens inermis. Annual, slender, branching, 2 feet high, hir- 

 sutely scabrous throughout : leaves ternately divided, the divisions 

 ternately or pinnately cleft into broadly linear segments, the terminal 

 one elongated : peduncles slender ; involucre hirsute, the outer bracts 

 narrowly linear, obtuse, the inner linear, acuminate, twice longer : ray 

 white faintly veined with purple, 5 lines long, neutral : achenes nu- 

 merous, unequal, very slender, mostly long-attenuate and 6 lines long, 

 scabrous above, awnless. — On rocky ledges in thin soil, Arroyo 

 Aucho, in the Sierra Madre, Chihuahua; C. G. Pringle (n. 1291), 

 Oct., 1887. Nearly allied to B. tenuisecta, but the achenes awnless 

 as in B. exaristata. 



Schkuhria (Euschkuhria) Pringlei. With the habit of the 

 genus, the leaves pinnately 3-7-parted with narrowly linear divisions, 

 the uppermost entire : bracts of the involucre obtuse, with scarious 

 yellow tips : flowers yellow : achenes (9) narrow, nearly 2 lines long, 

 slightly hairy on the angles ; pappus of very short unequal blunt 

 nerveless scales, the longer scarcely half the length of the glandular 

 base of the corolla. — In moist places on the plains near Guerrero, 

 Chihuahua; C. G. Pringle (n. 1292), Sept., 1887. 



Hymenothrix glandulosa. Annual or biennial, pubescent with 

 spreading gland-tipped hairs, 2 feet high or more : leaves twice or 

 thrice pinnate, the segments linear, obtuse : heads cymose ; involucral 

 bracts yellowish and somewhat scarious-margined : rays none ; corolla 

 of the disk-flowers with a dilated deeply lobed limb : achenes rather 

 broadly obpyramidal and prominently angled, somewhat pubescent and 

 hairy on the angles ; pappus-scales very short and blunt, unequal, 

 nerveless, not half the length of the glandular-hispid corolla- tube. — 

 By springs in the Sierra Madre, Chihuahua, at 9,000 feet altitude ; 



