34 NORTH AMERICAN FLORA [Volume 34 



2. Picradeniopsis Woodhousei (A. Gray) Rydb. Bull. Torrey Club 



37: 333. 1910. 



Achyropappus Woodhousei A. Gray, Proc. Am. Acad. 6: 546. 1865. 

 Schkuhria Woodhousei A. Gray, Proc. Am. Acad. 9: 199. 1874. 

 Bahia Woodhousei A. Gray, Proc. Am. Acad. 19: 28. 1883. 



A low suffruticose perennial; stem branched, slightly angled, grayish-puberulent ; 

 leaves opposite, 3-cleft into linear, obtuse divisions, grayish-strigulose, distinctly punctate; 

 heads short-peduncled; involucre turbinate, 5-6 mm. high, 6-8 mm. wide; bracts 8-10, 

 oblong, obtuse, puberulent; ligules 6-8, oblong, 3 mm. long, white or ochroleucous ; disk- 

 flowers about 20; corollas 3 mm. long; achenes 4 mm. long, elongate-obpyramidal, hirsutu- 

 lous; squamellae narrowly lanceolate, with a strong rib, acute. 



Type locality: New Mexico. 

 Distribution: New Mexico and Arizona. 



27. BAHIA Lag. Gen. & Sp. Nov. 30. 1816. 



Stylesia Nutt. Trans. Am. Phil. Soc. II. 7: 377. 1841. 



Virletia Schultz-Bip. ; Benth. & Hook. Gen. 2: 403, as synonym. 1873. 



Annual or perennial herbs or rarely undershrubs. Leaves opposite or alternate, or both, 

 more or less dissected, not conspicuously punctate. Heads in leafy corymbs. Involucre hemi- 

 spheric or turbinate ; bracts in 2 or 3 series, mostly oblanceolate, not keeled, sometimes slightly 

 petaloid on the margins. Ray-flowers usually present, pistillate, fertile, with linear ligules. 

 Disk-flowers many, hermaphrodite and fertile; corolla- tube glandular; throat campanulate. 

 Achenes elongate, narrowly obpyramidal, often hirsutulous on the angles below. Pappus of 

 a crown of 8-10 squamellae, which are either callous at the base, or with a midrib, sometimes 

 produced into an awn-tip. 



Type species, Bahia ambrosioiies Lag. 



Leaves not tomentose-canescent. 



Squamellae without distinct midribs, merely callous-thickened at the base ; 

 leaf -segments linear-filiform or filiform, glabrous or hirsute, more or 

 less impressed-punctate. 

 Annuals. 



Squamellae of the fruit much shorter than the corolla-tube; ligules 



5 mm. long. 1. B. Bigelovii. 



Squamellae of the fruit equaling the corolla-tube; ligules 3 mm. long. 2. B. Schaffneri. 

 Perennials. 



Perennial with a thick tap-root; bracts in 2 series. 3. B. xylopoda. 



Perennial with a slender rootstock; bracts in 3 series. 4. B. Pringlei. 



Squamellae with distinct midribs often excurrent; leaf -segments oblong or 

 obovate to linear-filiform, not at all punctate. 

 Perennials; bracts acute. 5. B. Ehrenbergii. 



Annuals; bracts obtuse. 



Plant cinereous-puberulent, if somewhat glandular the glands sessile. 

 Leaf -segments broad, obovate to oblong; midribs of the squa- 

 mellae not excurrent. 6. B. pedata. 

 Leaf -segments narrow, linear-filiform to oblong; midribs of the 

 squamellae often excurrent. 

 Plant erect; involucre 4—5 mm. high. 7. B. bitemata. 

 Plant branched at the base; branches spreading and decum- 

 bent at the base; involucre 6-7 mm. high. 8. B. aristata. 

 Plant conspicuously glandular with stipitate glands. 9. B. glandulosa. 

 Leaves tomentose-canescent; perennial, suffruticose at the base. 



Leaf -segments narrowly linear; bracts narrowly oblanceolate. 10. B. absinthifolia. 



Leaf -segments lanceolate to broadly linear; bracts broadly oblanceolate. 11. B. dealbata. 



1. Bahia Bigelovii A. Gray, in Torr. Bot. Mex. Bound. 96. 1859. 



Schkuhria Bigelovii A. Gray, Proc. Am. Acad. 9: 199. 1874. 



A branched annual; stem 2-4 dm. high, hirsutulous; leaves short-petioled, opposite, once 

 or twice ternately dissected into linear-filiform divisions, sparingly hirsutulous and distinctly 

 glandular-punctate, 3-5 cm. long; involucre nearly hemispheric, 5-6 mm. high, 8-9 mm. 

 broad, hirsute and glandular-punctate; bracts 8-9, obovate or the outer oblong, abruptly 

 short-acuminate; ligules 5-8, yellow, oblong or elliptic, 5 mm. long; disk-flowers 20-30; co- 

 rollas 2 mm. long, the glandular tube shorter than the deeply campanulate throat; achenes 



