1310 CICHOKIACEAE 



bracts in several series, dry, leathery or parchment-like. Receptacle flat, naked or rarely 

 pubescent or fimbrillate. Corollas rose-purple, white or rarely blue, all 2-lipped, those at 

 the margin of the disk with larger lower lips. Stigmas flattened, truncate or brush-like. 

 Achenes terete or slightly angled, usually papillose-puberulent, sometimes narrow near the 

 apex, but not beaked. Pappus of numerous scabrous, sometimes .rigid hair-like bristles. 



Caulescent: leaf-blades merely toothed. 1. P.nana. 



Acaulescent : leaf-blades runcinate-pinnatifid. y~ 2. P. runcinata. 



1. Perezia nana A. Gray. Caulescent, the foliage glabrous. Leaves alternate ; 

 blades parchment-like, orbicular to ovate or obovate, 2.5-5 cm. long, spiny-toothed, sessile 

 and partly clasping : involucre lax ; bracts ovate to oblong-ovate and broadly linear, the 

 outer 4-5 mm. long, the inner 10-15 mm. long : achenes 5-5.5 mm. long. 



On dry plains and rocky bluffs, southern Texas to Arizona and Mexico. Spring to fall. 



2. Perezia runcinata Lag. Acaulescent, the foliage scabrous-pubescent or glabrate. 

 Leaves basal ; blades papery, oblong to oblanceolate in outline, 5-20 cm. long, runcinate- 

 pinnatifid, the segments spinulose-fringed : involucres lax ; bracts mainly oblong to lanceo- 

 late and linear, with acuminate or bristle tips, the outer 3-4 mm. long, the inner some- 

 times 20 mm. long : central corollas purple, the tube about 1 cm. long : achenes 5-6 mm. 

 long. 



In dry soil, Texas and adjacent Mexico. Spring and summer. 



FAMILY 3. CICHORIACEAE Eeichenb. CHICORY FAMILY. 



Annual or perennial scapose or caulescent herbs, with a bitter acrid or milky 

 sap. Leaves alternate, sometimes all basal ; blades entire, or variously toothed 

 or parted. Flowers perfect, all alike in peduncled or rarely sessile involucrate 

 heads. Involucres of 1 or several rows of bracts. Receptacle flat or flattish, 

 naked or scaly, smooth, pitted or honeycombed. Pappus of scales or hair-like or 

 plumose bristles, sometimes both together. Corollas gamopetalous, commonly 

 yellow, sometimes white, pink, blue, or purple : tubes variable in length ; limb 

 a strap-shaped usually 5-toothed ligule. Anthers connate around the style : sacs 

 sagittate or auricled at the base, not tailed, usually appendaged at the top. 

 Pollen-grains mostly 2-sided. Ovary 1-celled. Stigmas 2. Ovules solitary, ana- 

 tropous. Fruit an achene. Seed erect. Endosperm wanting. Embryo with 

 the radicle narrower than the cotyledons. 



Pappus of simple hair-like bristles. 

 Achenes smooth or merely papillose. 

 Achenes cylindric or prismatic. 

 Achenes narrowed at the base. 

 Top of achenes truncate. 



Disks or ligules pale, cream-color or purple. 1 NABALUS. 



Disks or ligules yellow, orange or red. 2. HIERACIUM. 



Top of achenes narrowed or beaked. 



Pappus-bristles surrounded by a ring of villous hairs at the base, re- 

 ceptacle naked. 3. SITILIAS. 

 Pappus-bristles not surrounded by a ring of hairs ; receptacle chaffy. 4. PINAROPAPPUS. 

 Achenes terete, cylindric, not narrowed at either end. 5. LYGODESMIA. 

 Achenes flattened. 



Achenes narrowed at the top or beaked. 6. LACTUCA. 



Achenes truncate at the top. 7. SONCHUS. 



Achenes tuberculate or spinulose, or with spine-like processes. 8. TARAXACUM. 



Pappus of scales, or scales and bristles, or wanting. 



Pappus at least in part of plumose bristles. 9. TRAGOPOGON. 



Pappus of scales or of both scales and bristles or wanting. 

 Disk and ligules yellow or orange. 



Pappus of broad scales, with or without bristles. 10. ADOPOGON. 



Pappus wanting or obsolete. 11. SERINEA. 



Disk and ligules white, pink, blue or purple. 12. CICHORIUM. 



1. NABALUS Cass. 



Perennial caulescent herbs with racemosely or paniculately branched stems. Leaves 

 alternate : blades toothed, lobed or pinnatifid, sometimes divided, petioled or the upper 

 ones clasping. Heads small, usually nodding, often clustered. Involucres narrow, cylin- 

 dric, double ; inner of 1 or 2 series of nearly equal bracts ; outer of few very small bracts. 

 Keceptace flat, naked. Corollas pale, cream-colored or purplish ; ligules truncate and 

 toothed at the apex. Anthers sagittate at the base. Stigmas slender. Achenes oblong to 



