178 COMPOSITE. (COMPOSITE FAMILY.) 



few-flowered, themselves aggregated Into a compound or dense c.u&ter. . No 2. 

 Heads separate, few-flowered or many-flowered. 



Receptacle (when the flowers are pulled off) bristly hairy 67,68,70. 



Receptacle deeply honeycomb-like. . 69. 



Receptacle naked. 



Pappus of plumose or bearded stiff bristles. Flowers purple 4. 



Pappus of very plumose bristles. Flowers whitish. 6. 



Pappus of slender but rather stiff rough bristles. . . . . 6, 7, 8, 20. 



Pappus of very soft and weak naked bristles. . . . . . . 62, 63. 



i- t- Pappus composed of scales or chaff. 



Receptacle naked. Leaves in whorls. . 3. 



Receptacle naked. Leaves alternate. . . 45. 



Receptacle bearing chaff among the flowers 49. 



-(-- Pappus of 2 or few barbed awns or teeth, . . -41, 42. 

 -- i- Pappus none, or a mere crown-like margin to the fruit. . 6. 



* * Flowers of two kinds in the same head. 



Marginal flowers neutral and sterile, either conspicuous or inconspicuous. . . 66, 66. 

 Marginal flowers pistillate and fertile. 



Receptacle elongated and bearing broad chaff among the flowers. . . . .60. 



Receptacle naked or bearing no conspicuous chaff. 



Pappus of capillary bristles. Involucre imbricated 23, 58, 59. 



Pappus of capillary bristks. Involucre merely one row of scales. . 14, 61. 



Pappus obsolete or none. 



Achenia becoming much longer than the involucre 11. 



Achenia not exceeding the involucre 29, 56, 57. 



* * * Flowers of two kinds in separate heads ; one pistillate, the other staminate. 



Heads dioecious ; both kinds many-flowered. Pappus capillary 24, 59. 



Heads monoecious ; the fertile 1 - 2-flowered and closed. Pappus none. . . . 30, 3L 



$ 2. Rays present ; i. e. the marginal flowers or some of them with ligulate corollas. 

 * Pappus of capillary bristles. (Rays all pistillate.) 



Rays occupying several rows, ... 9, 10, 14 



Rays in one marginal row, and 



White, purple or blue, never yellow. 12-15. 



Yellow, of the same color as the disk. 



Pappus double, the outer short and minute. 21. 



Pappus simple. 



Scales of the involucre equal and all in one row. Leaves alternate. . . 63. 



Scales of the involucre in 2 rows. Leaves opposite 64. 



Scales of the involucre imbricated. Leaves alternate 19, 22. 



* * Pappus a circle of chaffy scales, dissected into bristles. ... 44. 

 * * Pappus a circle of thin chaffy scales or short chaffy bristles. 



Ueedfl several-flowered. Receptacle chaffy 50. 



Heads 8 - 10-flowered. Receptacle naked 13. 



Heads many-flowered. Receptacle deeply honeycombed. ..*... 48. 



Heads many -flowrrnl. Un .-ptuclc naked. . 46,47. 



* * * Pappus none, or a cup or crown, or of 2 or 3 awns, teeth, or chaffy scales corresponding 

 with the edges or angles of the achenium, often with intervening minute bristles or scales. 



- Receptacle naked. 

 Achenia flat, wing margined. Pappus of separate little bristles or awns. 16 



Achenia flat, margiulcss. Pappus none. Receptacle conicaL 17. 



Acheuia terete or angled. Pappus none. Receptacle flattish. . 64. 



Achenia angled Pappus a little cup or crown. Receptacle conicaL . 66. 



