CARDUACEAE. 185 



throat and a longer tube; lobes short. ot>. Fi.averia. 



Bracts of tlu> iuvolucre spreading or reflexed. ;i7. HeleniuM. 



Plant-tissues, especially the leaves and bracts of the 



involucre with oil-glands. 38. Pectis. 



Tribh VII. SENECIONEAE. 



Disk-flowers perfect : marginal flowers pistillate. .'!!1. Ekechtites. 



Disk-flowers and marginal flowers perfect. 



Disk cream-colored or greenish : corolla-throat much 



shorter than the tube. 40. Mesadema. 



Disk golden, orange or purple : corolla-throat about 



as long as the tube. 41. E.milia. 



'liunH VIII. CYNAREAE. 

 Plants with spine-margined leaves. 42. CiRSiUM. 



TitiBE IX. MUTISIEAE. 

 Heads with radiate marginal flowers. 43. Chaptalia. 



1. VERNONIA L. Caulescent herbs. Leaves alternate: blades mostly 

 toothed. Heads not involuurate. Corolla-lobes lanceolate. Anther-appendages 

 lanceolate to oblong. Pappus double, the outer series of scales or stout bristles, 

 the inner of numerous capillary bristles. 



1. V. Blodgettii Small. Stems 2-8 dm. tall: leaf-blades oblong to linear, 2-4.5 

 cm. long, entire: involucres 6-7 mm. high; inner bracts oblong or ovate- 

 oblong, acute: corolla purple. — Everglades and pinelands. — F, K. — Ironweed. 



2. ELEPHANTOPUS [Yaill.] L. Perennial scapose or caulescent herbs. 

 Leaves alternate: lilades shallowly toothed. Heads involucrate. Corolla-lobes 

 linear-lanceolate. Anther-appendages deltoid to ovate. Pappus single or 

 double, of several rigid bristles terminating scale-like bases. 



1. E. tomentosus L. Stems 2-7 dm. tall, mostly hirsute above: blades of the 

 basal leaves oblong, oval, or oblong-oblanceolate, crenate-serrate : inner bracts 

 of the involucre acuminate: bases of the pappus-bristles as long as the breadth 

 of the achene. — Pinelands. — Elephant "s-foot. 



3. EUPATORIUM [Tourn.] L. Caulescent herbs or shrubs. Leaves 

 alternate or opposite: blades entire, toothed, or dissected. Heads borne in 

 corymbs. Involucre campanulate to cylindric. Corolla-lobes ovate or triangu- 

 lar. Anther-appendages ovate. Achene angled. Pappus of capillary bristles. 

 — Thoroughwort. 



Leaf-blades dissected into filiform or narrow segments. 

 Leaf-segments filiform or nearly so. 



Inflorescence-branches secund-recurved : inner involucral bracts prominently 

 scarious-margined. gradually long-aristate. 1. E. leptophyUum. 



Inflorescence-branches fastigiate : inner involucral bracts 



obscurely scarious, abruptly short-aristate. 2. E. capillifoUum. 



Leaf-segments flat, mostly linear. 3. E. Eugcnei. 



Leaf-blades merely toothed or incised. 



Shrub. 4. E. rillosiim. 



Herbs. 



Involucral bracts acute: heads ."-flowered. 5. E. mikanioides. 



Involucral bracts obtuse : heads more than 5-flowered. 

 Involucral bracts very unequal : corollas 3 mm. long 

 or less : achenes 2 mm. long or less. 

 Leaf-blades sessile or nearly so : pappus thrice as 



long as the achene. 0. E. rccurvans. 



Leaf-blades long-petioled : pappus less than twice 



as long as the achene. 7. E. scrotinum. 



Involucral bracts nearly equal : corollas 4 mm. long : 



achenes 2..5 mm. long. H. E. jiicumlum. 



