Descriptive Flora 



209 



Page 



o. Stems hollow Senecio — 240-1 



p. Stems not hollow Xanthisma — 219 



(y) Stems hairy. 



(1) Rays 4—5, stems coarse . . . . Lindheimera — 227 



(2) Rays usually 8. 



o. Leaves crenate . . . Berlandiera — 226-7 



p. Leaves lobed Engelmannia — 227 



( 3 ) Rays usually more 



than 8. 



o. Leaves small, finely 



segmented .Thymophylla — 239 



p. Leaf stalks with tooth- 

 ed appendage at base. . .... .Ximenesia — 232 



q. Leaves strong-scented 



when crushed ♦ . . Heterotheca — 218 



b. Flowers pink to red. 



x. Sap milky Lygodesmia — 245 



y. Sap not milky. 



(m) Leaves all basal, heads on long 



naked stalks . Gaillardia — 239 



(n) Leaves not all basal, 

 r. Plants thistle-like. 



(1) Leaves woolly underneath Cirsium — 242 



(2) Leaves not woolly under- 

 neath Perezia — 243 



s. Plants not thistle-like. 



1. Rays drooping, disk columnar Ratibida — 229 



2. Rays not drooping, 

 o. Leaves entire. 



(1) Flowers in a dense 



spike Lacinaria — 215 



(2) Flowers not in a spike Polypteris — 236 



p. Leaves not entire. 



(1) Leaves prickly-edged Perezia— 243 



(2) Leaves not prickly- 



edged, rays partly 



colored red and yellow Gaillardia — 238 



c. Flowers white or shading into blue, 



pink and purple, 

 m. Sap milky Pinaropappus— 244 



