232 CARDUACEAE 



Leaves slender-petioled, not spinulose-toothed ; bracts tliin, 2 mm . wide or less. 

 Heads 30-oO-flowered. 



Lea^'es tliin, minutely puberulent; their teeth usually broadly triangular, 



acute: peduncles usually longer than the heads. 2. C. grandiflorus. 



Leaves thicker, densely scabrous-pubescent, veuay, their teeth rounded-ovate, 

 obtuse or niucronate. 3. C. umbellalus. 



Heads 9-2o-flowered. 



Tips of the bracts not spreading; leaf-blades 2-5 cm. long. 

 Leaves distinctly petioled; blades subcordate, 2-5 cm. long. 



Leaves Arm, crenate-dentate. 4. C. albjcaulis. 



Leaves tliin, crenate. 5. C tener. 



Leaves short-petioled ; blades lanceolate, 1-4 cm. long. 6. C. brachyphyllus. 

 Tips of the bracts squarrose-spreading ; leaf-blades less than 1 cm. long. 



Leaves on the peduncles many, passing into the bracts; inner bracts much 

 longer than the outer ones; upper parts of the plant velutinous and 

 glandular. 

 Stem and pedicels glandiilar- villous ; head about 13 mm. high, 20-24- 



flowered; achenes 4-4.5 mm. long. 7. C. microphyllus. 



Stem lanulose; heads about 11 mm. high, about 1-8-flowered; achenes 

 about 3.5 mm. Jong. 8. C. Watsonii. 



Leaves on the peduncles few; bracts gradually increasing in length up- 

 wards; plant scabrous-puberulent. 9. C. scaber. 

 I^eaves linear or oblong, sessile. 

 Heads 30-40-flowered. 



Achenes glandular; bracts comparatively firm. 10. C. oblongif alius. 



Achenes hispidulous on the angles, not glandular; bracts thin. 



11. C. linifoU'js. 

 Heads 3-5-flowered. 12. C. longifoiius. 



5. KUHNIA L. False Boneset. 



Leaves oblong or lanceolate. 3-ribbed, more or less toothed. 

 Leaves densely puberulent beneath. 



Inner bracts abruptly acute or cuspidate. 1. K. glutinosa. 



Inner bracts gradually acuminate. 2. K. Hilchcockii. 



Leaves glabrous or nearly so beneath. 3. K. reticulata. 



Leaves linear, 1-ribbed, entire. • 4. A', leptopliylla. 



6. LACINIARIA Hill. Blazing Star, Button Snake-root. 



Pappus plumose. 



Heads 15-60-fiowered; corolla-lobes hairy within. 1. L. squarrosa. 



Heads 4-6-flowered; corolla-lobes glabrous within. 2. L. punctata. 



Pappus merely barbellate. 



Heads few, hemispheric, 15-45-flowered. 



Heads m a short raceme-like or corymbiform inflorescence; bracts obovate, with 



a dark rose-pm-ple lacinlate ape.x; leaves usually glabrous. 8. L. ligulistylis. 

 Heads in a long spike-hke inflorescence ; bracts spatulate or obovate-oblanceolate , 

 with a pale merely erose ape.x; leaves usually liispidulous or crisp-hairy. 



4. L. aspera. 

 Heads oblong, 3-15-flowered, niunerous in a long spike. 



Bracts obtuse, appressed. ■ 5. L. spicata. 



Bracts acute, their tips spreading. 6. L. pycnostachya. 



7. GUTIERREZIA Lag. Brown-weed. 



Disk- and ray-flowers in the head 4-7 each. 



Surface of the leaves marked with large dots, each bordered by a hyaline scale. 



1. G. lepidota. 

 Surface of the leaves not lepidote, either puberulent or glabrous. 



Axils of the leaves with fasciculate branches. 2. G. fasciculata. 



A.xils of the leaves without fasciculate branches. 



Plant Ugneous only at the short persistent caudex. 

 Leaves linear, usually 1.5—4 mm. wide. 



Involucres oblong-turbinate, over 5 mm. high; outer bracts lanceolate; 



stems 3-4 dm. high. 3. G. scoparia. 



Involucres camj^anulate, somewhat turbinate at the base, less than 5 

 mm. liigh; bracts ovate; stems 1-2 dm. high. 4. G. diversifolia. 



Leaves linear -fihform. less than 1 mm. wide. 



Ligules of the rays nearly as long as the involucre. 5. G. fili folia. 



Ligules of the rays about half as long as the involucre. 



Heads usually peduncled and soUtary at the ends of the branches. 



6. G. divaricate. 

 Heads usually subsessile in clusters of 3-4 at the ends of the branches. 



Plant low, 1-2 dm. high; branches green; leaves 1-2 cm. long. 



7. G. juncca. 

 Plants 2-5 dm. high; branches with straw-colored or gray bark; 



leaves 3-4 cm. long. 8. G. Sarothrae. 



Plant shrubby. 



Involucres elongate, clavate-turbinate, 2-3 mm. wide; bracts oblong. 



9. G. lomjifolia. 

 Involucres campanulate, only slightly turbinate at the base, 3-4 mm. wide: 

 outer bracts ovate or obovate. 10. G. linearis. 



Disk- and ray-flowers in the head only 1-2 each. 11. G. glomerella. 



