178 COMPOSITE, (composite family.) 



Heads few-flo'^ered, themselves aggregated into a compound or deoee closter. . Ko. 2. 

 Heads separate, few-flowered or many -flowered. 



Receptacle (when the flowers are piilled 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, 5. 



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



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



•I- •»- Pappus composed of scales or chaff. 



Receptacle naked. Leaves in whorls 3. 



Receptacle naked. Leaves alternate. . 45. 



Receptacle bearing chaff among the flowers 49, 



■t- •*- +- Pappus of 2 or few barbed awns or teeth. . . .41, 42. 

 -1- -f- -t- ^- Pappus none, or a mere crown-like margin to the fruit. . 55- 



* * Flowers of two kinds in the same head. 

 Marginal flowers neutral and sterile, either conspicuous or inconspicuous. . 65, 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 bristles. 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. . . 80, 31. 



§ 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 cue 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. 



ScaJes 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, 23. 



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



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

 Heads several-flowered. Receptacle chaffy. . . . .... 50. 



Heads 8-10-flowered. Receptacle naked. . IS. 



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



Heads many-flowered. Receptacle 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, marginless. Pappus none. Receptacle conical 17. 



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



Achenia angled. Pappus a little cup or crown. Receptacle conical. . 55. 



