Helianthus. composite. 333 



cultivated for a very long period for its fleshy tubers. — Rays 12-15. Pappus 

 of 1 to 4 subulate scales or chaflTy awns. — Jerusalem Artichohc. 



H. negkctus, Hort. Berol. 1840; we have seen no descrijotion of this species. Is 

 it H. rigidus '] 



H. villosus, Nutt. is enumerated in Loud. hort. Brit., but no-where described. 



98. HELIANTHELLA. 



Heads many-flowered ; the ray-flowers 10-24, neutral ; those of the disk 

 perfect. Scales of the involucre linear or lanceolate, in about 2 series, loose, 

 somewhat foliaceous. Chaff of the receptacle persistent, embracing the 

 achenia. Corolla of the disk cylindrical, elongated, 5-toothed, with a very 

 siiort proper tube. Branches of the style very hispid, more or less obtuse. 

 Ovary comjjressed, with one or both margins slightly winged and produced 

 at the summit into a short auriculate and lacerate persistent appendage or 

 into an awn, sometimes with intermediate squamellse, or an obscure coroni- 

 form fringe, glabrous, or ciliate. — Perennial herbs, with linear or lanceolate 

 mostly scattered and sessile entire leaves, and solitary showy heads termina- 

 ting the stem or branches. 



§ 1. Receptacle convex : apj^endages of the style slender, hispid throughout, 



1. H. grandiflora : stem simple, leafy, scabrous-pubescent; leaves lan- 

 ceolate-linear, 1-nerved, scabrous-hispid ; scales of the involucre lanceolate, 

 acute, somewhat appressed, about the length of the disk ; rays 16-20, elon- 

 gated ; chafl" of the receptacle as long as the corolla, obscurely 3-toothed ; 

 immature achenia oval, compressed, glabrous, with 2 obtuse auricles at the 

 summit, which are somewhat lacerate-fringed, and often bear one or more 

 minute and deciduous aristate squamellae, the whole summit crowned with a 

 ring of minute hairs; the inner edge slightly winged. 



East Florida, Dr. Leavenworth ! Dr. Burrows! — Stem apparently 3-4 feet 

 high, the base wanting. Leaves without order, sometimes nearly opposite, 

 2-4 lines wide, obtuse at the base : the lower 2 inches, the uppermost scarce- 

 ly an inch long. Disk nearly an inch in diameter ; the rays sometimes 2 

 inches long. Corolla sparsely hairy towards the base, the teeth nearly gla- 

 brous. The two gibbosities or auricles of the achenia resemble the pappus of 

 some species of Coreopsis ; that which is formed by the prolongation of the 

 inner and wing-like margin of the achenium is often largest : there are no 

 intermediate stjuaraells, but a crown-like minute ring of bristles which 

 probably takes their place : the small awns or squamella3, when present, 

 arise from within the auricles. 



2. H. tenuifolia : stem slender, scabrous, simple, or branching at the sum- 

 mit; leaves very narrowly linear, 1-nerved, very scabrous ; scales of the in- 

 volucre lanceolate-subulate, loose, hirsute, as long as the disk; rays 10-12; 

 chaff oblong, 3-lobed, shorter than the corolla ; achenia glabrous, short, quad- 

 rangular ; the anterior and posterior angles strongest or somewhat margined, 

 each produced at the summit into a stout persistent chafiy tooth, the interme- 

 diate angles obscurely toothed. 



Sand hills, Middle Florida, Dr. Chapiman ! — Leaves 2 inches or more in 

 length, less than a line wide. Heads not half the size of the preceding. 

 Disk-corolla short, glabrous; the proper tube very short and indurated. 



