46 NORTH AMERICAN FLORA [V01.UME 34 



sparingly puberulent; involucre 5 mm. high, 4 mm. broad; bracts 4, obovate, keeled, 

 yellow at the apex; ray-flowers solitary or often wanting; ligule obovate, short, not longer 

 than the disk-corollas; disk-flowers 3-5; corolla-tube glandular; limb 4-lobed; achenes 

 densely villous on the angles, obpyramidal, about 4 mm. long; squamellae unequal, those of 

 the angles ovate, awn-pointed, equaling the corolla, the intermediate ones shorter, muticous. 



Type locality : Around Cosiquiriachi in the Sierra Madre west of Chihuahua. 

 Distribution: Arizona and Chihuahua. 



7. Tetracarpum flavum Rydberg, sp. nov. 



A slender annual; stem about 3 dm. high, sparingly glandular-puberulent ; leaves alter- 

 nate, 2-4 dm. long, pinnatifid into 3-5 narrowly linear divisions or the upper entire, conspicu- 

 ously punctate, glabrate; peduncles 2-4 cm. long; involucre 6-7 mm. high, 5-6 mm. broad; 

 bracts about 5, obovate, punctate and minutely puberulent, keeled, with light-yellow margins 

 and tip; ligule 2-3 mm. long, oblong, light-yellow; disk-flowers 4-6; corollas 3 mm. long; 

 achenes elongate, obpyramidal, 5 mm. long, densely villous-hirsute on the angles, sUghtly so on 

 the striate faces; squamellae unequal, those of the angles lanceolate, aristate, fully as long as 

 the corollas, the intermediate ones about half as long and acute. 



Type collected in Sierra de San Felipe, Oaxaca, October 10, 1894, Charles L. Smith 263 b' 626 

 (herb. N. Y. Bot. Gard.). 



8. Tetracarpum schkuhrioides (Link & Otto) Rydberg. 



Achyropappus schkuhrioides Link & Otto, Ic. PI. Rar. pi. 30. 1829. 



Bahia schkuhrioides A. Gray, Proc. Am. Acad. 19: 27. 1883. 



Schkuhria senecioides Nees, Del. Sem. Hort. Bonn. 1831.— DC. Prodr. 5: 654, as synonym. 1836. 



Schkuhria schkuhrioides Thellung, Repert. Sp. Nov. 11: 308. 1912. 



A slender annual; stem erect, 3-6 dm. high, glabrate, strongly grooved; leaves alternate, 

 3-7 cm. long, bipinnatifid into linear or linear-filiform divisions, glabrous or nearly so, im- 

 pressed- punctate ; involucre turbinate, 5 mm. long, 6 mm. broad, glabrous, glandular-punctate; 

 bracts 6-8,- obovate, with yellow scarious margins and tips, subtended by 1-3 smaller ones; 

 ligules 1-4, broadly oblong or cuneate, 4 mm. long; disk-corollas many, 3 mm. long; achenes 

 narrowly obpyramidal, 3 mm. long, hispidulous on the angles; squamellae obovate, 6.5 mm. 

 long, slightly thickened on the back; without distinct costa. 



Type locality: Mexico. 



Distribution: Central and southern Mexico. 



Illustration: Link & Otto, Ic. PI. Rar. pi. 30. 



EXCLXJDED SPECIES 



Schkuhria abrotanoidES Roth has been reported erroneously from Mexico by Hemsley: 

 Caleotti 2045 belongs to Tetracarpum Wislizeni; Mueller 270 belongs to T. anthemoideum; 

 Bourgeau 372 and Coulter 314 belong to T. virgatum. 



35. CEPHALOBEMBIX Rydberg, gen. nov. 



Slender glandular-hirsutulous annuals. Lower leaves opposite, the upper alternate, 

 pinnately dissected into linear-filiform divisions, hirsutulous and impressed-punctate. Heads 

 discoid, many in leafy corymbs. Involucre turbinate or obconic ; bracts 5-8, obovate, somewhat 

 convex but not keeled, herbaceous, hirsutulous and somewhat punctate, scarious and more or 

 less colored around the margin. Rays wanting. Disk-flowers Hght-yellow; tube glandular, 

 slender, equaling or exceeding the funnelform throat; lobes oblong. Style-branches with 

 short acute appendages. Achenes elongate-obpyramidal, 4-angled, hispidulous on the angles 

 especially below. Pappus of 8 scarious squamellae either callous-thickened at the base or 

 with prominent midrib. 



Type species, Schkuhria neomexicana A. Gray. 



1. Cephalobembix neomexicana (A. Gray) Rydberg. 



Schkuhria neomexicana A. Gray, Mem. Am. Acad. II. 4: 96. 1849. 

 Amhlyopappus neomexicanus A. Gray, in Torr. Pacif. R. R. Rep. 4: 106. 1857. 

 Bahia neomexicana A. Gray, Proc. Am. Acad. 19: 27. 1883. 

 Achyropappus neomexicanus A. Gray; Rydb. Fl. Colo. 377. 1906. 



