148. COMPOSlTAE. 20s". 



60. Heads with female and male (apparently hermaphrodite) 



flowers. Female corollas strap-shaped or thread-shaped. 



39 PARTHENIUM. 

 Heads unisexual. 61. 



61. Female heads 2 flowered. 40 XANTHIUM. 

 Female heads 1 flowered. 52 AMBROSIA. 



62. Pappus of outer fruits 0, or if present, not of bristles. 63. 

 Pappus of outer fruits consisting of bristles. 67. 



63. Outer flowers with a strap-shaped corolla. 64. 



Corolla of outer flowers tubular or wanting. 66. 



64. Corolla of outer flowers very shortly strap-shaped, of inner 



4-toothed. Involucre in 2 rows. (Cenia.) 58 COTULA. 

 Corolla of outer flowers distinctly strap-shaped. Involucre 

 rarely in 2 rows and then corolla of inner flowers 5- 

 toothed. ' 65. 



65. Style branches pointed or style undivided. Flowers blue, rare- 

 ly white. 74 GARULEUM. 

 Style branches truncate. Fruits 5 — 10 ribbed. 



56 CHRYSANTHEMUM. 



66. Corolla of inner flowers 2-4-toothed. 58 COTULA. 

 Corolla of inner flowers 5-toothed. 62 ARTEMESIA. 



67. Pappus of 1 or 2 rows of bristles. 68. 

 Pappus (at least of outer fruits) of 3 or more rows of bristles. 



72. 



68. Involucre bracts free in 1 row. 85 CINERARIA. 

 Involucre bracts in 2 or more rows. 69. 



.69. Outer corollas thread-shaped (see 64 and 66). 58 COTULA. 

 Outer corollas strap-shaped. 70. 



70. Stem woody at the base. 8 FELICIA. 



Stem herbaceous. 71 



71. Involucral bracts in 2 rows. 9 ERIGERON. 

 Involucral bracts in 3 or more rows. 7 ASTER. 



72. Involucral bracts in several rows. 7 ASTER. 

 Involucral bracts in 1 row, sometimes surrounded by smaller 



ones. - '3. 



73. Style of central flowers 2 cleft (Othonoopsis). 67 HERTIA. 



Style of central flowers undivided. 70 OTHONNA. 



74. (53) Style branches of hermaphrodite flowers with hairs on the 



outer surface and below point of division. Stigmatic 



papillae on inner surface. 75. 



Style branches hairy chiefly in upper part, not below point 



of division. Stigmatic papillae marginal. 78. 



75. Pappus wanting. 1 ETHULIA. 



Pappus of scales or bristles. 76. 



76. Pappus of scales. 81 BERKHEYA. 

 Pappus of bristles. ''• 



