CARDUACEAE. 131 



Plants not dioecious : disk corollas with funnelform or catnpanulate throats : ray- 

 corollas, when present, with flat ligules. 

 Heads without ray-flowers. 



Achenes 3-5-angled, ribless : corolla-throat funnelform. 

 Bracts of the involucre leathery or parchment-like, in 



many series, striate. 1. OSMIA. 



Bracts of the involucre membranous or herbaceous, in 



1-few series, not striate. 2. EDPATORIOM. 



Achenes 10-ribbed : corolla-throat campanulate. 3. GARBKBIA. 



Heads with ray-flowers. 4. CHBYSOMA. 



Plants dioecious : pistillate corollas filiform ; staminate corollas 



funnelform. 5. BACCHARIS. 



1. OSMIA Sch. Bip. Shrubs or perennial herbs. Leaves opposite: blades 

 broadest below the middle. Heads borne in corymbs. Involucre ovoid or thick- 

 cylindric. Corolla-lobes ovate or rounded. Anther- appendages triangular. 

 Achene angled. Pappus of capillary bristles. 



Bracts of the involucre 5-7-ribbed : receptacle convex. 1. O. frustrate,. 



Bracts of the involucre 3-ribbed : receptacle flat. 2. O. odorata. 



1. O. frustrata (B. L. Robinson) Small. Stems 5-10 dm. tall, minutely 

 pubescent: leaf -blades ovate-lanceolate to deltoid-ovate, 2-3 cm. long, rather 

 obtuse: involucre 6-8 mm. long: corollas about 4 mm. long. [Eupatorium 

 heterodinum Chapm. Not. Griseb., Eupatorium frustratum B. L. Robinson.] 



Hammocks, F. Keys. (Endemic.) 



2. O. odorata (L.) Sch. Bip. Stems 6-18 dm. tall, pubescent: leaf -blades 

 ovate to lanceolate, 4-10 cm. long, acuminate: involucres 8-10 mm. long: 

 corollas about 5 mm. long. 



Hammocks, s. pen. Fla. and the F. Keys. (Cont., W. I.) 



2. EUPATORIUM [Tourn.] L. Shrubs or caulescent herbs. 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. 

 1. B. villosum Sw. Stems 5-20 dm. tall, tomentulose: leaf -blades ovate to 

 deltoid-ovate, 1.5-7 cm. long, obtuse, entire or repand: bracts of the involucre 

 obtuse, the inner 4 mm. long: corollas 3 mm. long: achenes 1.5-2 mm. long. 



Hammocks, E. Keys. (W. I.) 



3. GARBERIA A. Gray. Shrubs. Leaves alternate: blades broad, entire. 

 Heads borne in rather dense corymbose cymes. Involucre narrow. Corolla- 

 throat campanulate, rather shorter than the much narrower tube: lobes nar- 

 rowly lanceolate. Androecium conspicuously exserted: anther-appendages 

 notched. Achene long, ribbed. Pappus of scabro-barbellulate capillary bristles 

 in 2 or more rows. 



1. G. fruticosa (Nutt.) A. Gray. Stems 1-2 m. tall: leaf -blades spatu- 

 late to obovate, 2-3 cm. long: involucre 10-12 mm. long; bracts of the invo- 

 lucre puberulent: achenes 9-10 mm. long. 

 Hammocks, pen. Fla. (Endemic.) 



4. CHRYSOMA Nutt. Shrubs or partly woody plants. Leaves alternate : 

 blades narrow, fleshy-leathery, conspicuously fine-pitted. Heads numerous, 

 thyrsoid, or somewhat corymbose. Involucres narrow, few-flowered: bracts nar- 

 row, the inner much longer than the outer. Ray-flowers 1-3: corollas with a 

 long tube and a yellow ligule. Disk-corollas with a funnelform throat and a 

 tube of about equal length: lobes lanceolate. Anthers longer than the fila- 



