Order 70.— ASTERWORTS. 237 



25 S. Canaden'sls. Canada G. Leaves pointed, rongli. Panicle broad, c. 



26 S. Short^ii. Shorfs G. Leaves acute, very smooth. Panicle long, narrow. "W, 



87 S. pilo'sa. Hairy S. Hairy, 4-7f. high. Leaves remotely serrnhite. N.-J. S. 



28 S. odo'ra. Sweet S. Stem downy in lines, slender, 2-8t'. high. Leaves very en- 



tire, smooth, punctate with pellucid dots. Fragrant, c. 



29 S.tortifo'lia. Twut-lv.S. Stemrougli. Lvs. often twisted, not punctate. S. 



30 S. altis'sima. Tall S. Stem liairy, 4-6f. Lvs. veiny, rough. Scales acute. <7. 

 81 S.Tirammon'dai. Drummo lid's S. Stem l-2f. Lvs. velvety. Scales obtuse. W 

 S'2 S. rad'ula. Easp-lu. S. Stem rough-downy. Lvs. oblong-spatulate. VV. 



83 S. ulmifo'lia. Elm S. Branchlets hairy. Scales acute. Eays 3 or 4, disk flow- 



ers 3 or 4. N. W. 



84 S. Boot^ii. BooWs S. Branchlets Iruiry. Scales obtuse. Eays 2-.'>, disk flowera 



8-12. S. 



85 S. Unoi'des. Flax S. Smooth all over. Scales obtuse. Eays 1-4. 12-20^ N. 



36 S. Muhlenber''gu. Muhlenberg'' s S. Lvs. large, thin, notched, smooth both 



sides. Heads 15-flowered. N. 



37 S. patella. Spreading S. Lvs. large, thick, very rough on the upper side. 



Stem 2-4f, branches leafy. Heads 20-flowered. N. 



88 S. ellip'tica. Marsh S. Very leafy. Lvs. elliptic. Panicle dense, pyramidal, 



89 S. argu'ta. Saw-lv. C. Leaves few, elliptic, sharply serrate. Panicle spreading. 

 40 S. neglec'ta. Neglected S. Leaves few, serrate, lin. -lanceolate. Panicle narrow. 



41 S. Ohien'sis. Ohio S. Smooth all over. Lvs. obtuse, flat. Corymbed. W. 



42 S. RiddeFlii. RiddeWs S. Branches, &c., dust-downy. Lvs. acute, concave. 



Heads corymbed. W. 



43 S. corymbo^sa. Corymbed S. Branches corymbed, hirsute. Outer secund. 

 44 S. Houghto'nii. Houghton''s S. Hds. few, very large. Otherwise like No. 41. N.-W. 

 45S. rig'ida. Stiff S. Lvs. rigid. Heads very large. Scales obtuse. Height 3-5f. 

 46 S. Spithamae'a. Dwarf S. Leaves thin, sharp-serrate. Scales acute. Height 



6-12'. Mountains. S. 



47 S, lanceola'ta. Lance-lv. S. Leaves linear-lanceolate, 3-5-veined, Eays 



minute, about 17. Corymbs crowded, fragrant, c. 



48 S. tenuifo'lia. Linear-h. S. Leaves narrow-linear, one-veined. Eays short, 



about 10. More slender, with thinner clusters, c. 



2. HELTA N'THUS. Sunflower. 



Heads many-flowered, rays neutral, disk-florets perfect. Scales of the 

 involucre in several rows, more or less imbricated. Torus flat or convex, 

 the chaff persistent, embracing the 4-sided, flattened achenia. Pappus of 

 2 chatfy awns, deciduous. — Herbs, mostly 2^, rough. Leaves opposite, the 

 upper often alternate, mostly 3-veined. Heads mostly large, the disk 

 from half an inch to If. broad. Rays yellow, disk yellow or purple. July-' 

 O'lt. (Figs. 498, &c.) 



