SUNFLOWER FAMILY. 409 



herbage (the foliage sometimes gummy or resinous) and alternate leaves. 

 Receptacle naked. Bracts of the involucre commonly well imbricated. Disk- 

 flowers yellow (except in some Lessingias and Pentachaetas), perfect in all 

 ours except Baccharis. Rays present or absent. Anthers not caudate at base. 

 Pappus of awns or bristles (except Bellis). 



A. Flowers of both disk and ray yellow (except in Pentachaeta) ; rays present (except 

 in no. 83 and one species of nos. 78, 80 and 82). 



Pappus of several short scales; heads very small 76. Gutierrezia. 



Pappus of several caducous awns or bristles; heads large and very gummy; in- 

 volucral bracts often squarrose; leaves not narrow, mostly serrate; perennial 



herbs 77. Grindelia. 



Pappus of persistent bristles. 



Bristles 3 to 5 (sometimes obsolete) ; low annuals with filiform stems and leaves 



78. Pentachaeta. 

 Bristles many. 



Ray-achenes without pappus or the pappus a reduced crown 79. Heterotheca. 



Ray-achenes (when present) with pappus like that of disk. 



Pappus often of 2 kinds; the inner capillary, the outer very short and scale-like 



or obsolete 80. Chrysopsis. 



Pappus of one kind. 

 Evergreen shrubs. 



Heads solitary at the ends of the branches; pappus permanently white 



81. Stenotus. 



Heads in cymose or corymbose clusters; pappus in age reddish 



82. Ericamkria. 

 Suffrutescent or herbaceous plants; heads in corymbs or panicles. 



Rays none ; corolla throat ventricose 83. Isocoma. 



Rays present; corolla not ventricose 84. Solidago. 



B. Flowers yellow, white, or purple; rays none, but the outer corollas often enlarged and 



more deeply cleft on the inner side. 

 Heads small, turbinate or campanulate; pappus present, its bristles commonly numerous and 

 reddish brown in age; annuals 85. Lessingia. 



C. Flowers of the disk yellow (sometimes changing to purple); rays never yellozv, always 



present (but so inconspicuous as to appear wanting in one species of 



Aster and of Erigeron). 



Pappus none; heads on scape-like peduncles; rays white or pink-tinged; ours perennial 



herb 86. Bellis. 



Pappus of disk-achenes of numerous capillary bristles. 



Pappus reddish or rusty brown; pappus of ray scanty or none; perennial herbs 



87. Corethrogyne. 

 Pappus dull white; pappus of ray similar to disk. 



Bracts of the involucre mostly in 2 or more series, usually with herbaceous tips; 



rays usually numerous; perennial or annual herbs 88. Aster. 



Bracts of the involucre in 1 or 2 series, without distinctly herbaceous tips; rays very • 



numerous and narrow; perennial or biennial herbs 89. Erigeron. 



D. Flowers whitish or yellowish, dioecious; rays none. 

 Ours shrubs except one 90. Baccharis. 



Tribe 11. Eupatorieae. Eupatory Tribe. 



Ours herbs or suffrutescent plants with white or flesh-colored perfect disk- 

 flowers and no rays. Receptacle naked. Anthers not caudate at base. Style- 

 branches stigmatic only below the middle. 



Leaves opposite; pappus of awns and paleae 91. Trichocoronis. 



Leaves alternate; pappus of bristles only 92. Brickellia. 



Tribe 1. Cichorieae. Chicory Tribe. 

 1. CICHORIUM L. 

 Perennial herb, the leaves mostly radical, those of the stiff branching stem 

 reduced and bract-like. Flowers blue, in sessile heads. Receptacle without 

 bracts. Bracts of the obloflg involucres herbaceous, in 2 series, the outer 4 or 



