8QO FLORA. 



white flowers in involucrate heads (anthodia). Bracts of the involucre in I to sev- 

 eral series. Receptacle of the head flat or flatfish, naked, scaly (paleaceous), 

 smooth, pitted, or honeycombed. Flowers all alike (heads homogamous), perfect, 

 Calyx-tube completely adnate to the ovary, its limb (pappus) of scales, or simple 

 or plumose bristles, or both, or wanting. Corolla gamopetalous, with a short or 

 long tube, and a strap-shaped (ligulate) usually 5-toothed limb (ray). Anthers 

 connate into a tube around the style, the sacs sagittate or auricled at the base, not 

 tailed, usually appendaged at the summit, the simple pollen-grains usually 12-sided. 

 Ovary i-celled; ovule I, anatropous; style very slender, 2-cleft, of 2-lobed, the 

 lobes minutely papillose. Fruit an achene. Seed erect; endosperm none; radicle 

 narrower than the cotyledons. About 65 genera and 1400 species, of wide geo- 

 graphic distribution. The family is also known as LIGULIFLORAE, and is often 

 regarded as a tribe of the COMPOSITAE. 



* Pappus of scales, or of scales and bristles, or none (see No. 18). 

 Flowers blue or white ; pappus of blunt scales. i. Cichorium. 



Flowers yellow. 



Bracts of the involucre membranous, or herbaceous. 



Pappus none; achenes 2O-3o-nerved. 2. Lapsana. 



Pappus none ; achenes 8-io-ribbed. 3. Serinea. 



Pappus of rounded scales, with or without an inner series of bristles. 



4. Adopogon. 

 Bracts of the involucre thickened and keeled after flowering ; pappus none. 



5. Arnoseris. 

 * * Pappus, at least some of it, of plumose bristles. 



Receptacle chaffy. 6. Hypochaeris. 



Receptacle naked. 



Plume-branches of the pappus not interwebbed. 



Flowers yellow ; plants scapose, the leaves basal. 7. Leontodon. 



Flowers yellow ; plants leafy-stemmed. 8. Picris. 



Flowers pink. 9. Ptiloria. 



Plume-branches of the pappus interwebbed. 10. Tragopogon. 



* * * Pappus of simple bristles (of soft white scales with or without bristles in No. 18.) 

 \ Receptacle with a few deciduous bristles; flowers yellow, 



ii. Malacothrix. 

 ft Receptacle naked. 



1 . Achenes spinulose, or with short processes near the summit. 



Heads few- (6-15-) flowered, yellow; stem branching. 12. Chondrilla. 



Heads many-flowered, yellow, solitary on scapes. 13. Taraxacum. 



2. Achenes smooth, or papillose, not spinulose toward the summit. 



(a) Achenes flattened. 



Achenes truncate, not beaked ; flowers yellow. 14. Sonchus. 



Achenes narrowed at the summit, or beaked ; flowers blue or yellow. 15, Lactuca. 



(b) Achenes cylindric, or prismatic. 

 Achenes terete, not narrowed at the base; flowers pink or purple. 



16. Lygodesmia. 



Achenes narrowed at the base, narrowed or beaked at the summit ; flowers yellow. 

 Achenes slender-beaked. 



Pappus-bristles not surrounded by a villous ring at base. 



Pappus of slender simple bristle*. 17. Agoseris. 



Pappus of narrow soft scales, with or without some slender bristles. 



18. Nothocalais. 



Pappus-bristles surrounded by a villous whit? ring at base. 19. Sitilias. 

 Achenes merely narrowed above, not beaked. 20. Crepis. 



Achenes narrowed at the base, otherwise columnar, truncate (except in two species of 

 Hieracium}. 



Flowers yellow, orange, or red. 21. Hieracium. 



Flowers white, cream-colored, or purple. 22. Nabalus. 



i. CICHORIUM L. 



Erect branching herbs, with alternate and basal leaves, those of the stem and 

 branches usually very small and bract-like, and large heads of blue, purple, pink, or 

 white flowers, peduncled, or in sessile clusters along the branches. Involucre of 

 2 series of herbaceous bracts, the outer somewhat spreading, the inner erect and 

 subtending, or partly enclosing, the outer achenes. Receptacle flat, naked, or 

 slightly fimbrillate. Rays truncate and 5-toothed at the apex. Anthers sagittate 



