COMPOSITE. (composite family.) 145 



7. GRINDELIA, Willd. Gum-Plant. 



Herbs of coarse habit; with sessile or partly clasping and usually ser- 

 rate rigid leaves, and rather large heads of yellow flowers terminating the 

 branches ; the narrow rays numerous, occasionally wanting. Heads more or 

 less viscid, especially before blooming, but the herbage glabrous (in ours). 



* Akenes squarely truncnte and even at the summit, not toothed : pappus-awns 



2 or 3. 



1. G. squarrosa, Dunal. Commonly only a foot or two high and 

 branched from the base : leaves rigid ; cauline from spatulate- to linear-oblong 

 and with, half-clasping base, acutely and often spinulosely serrate or denticu- 

 late ; sometimes radical and even cauline laciniate-pinnatitul : involucre strongly 

 scpiarrose with the spreading and recurving short-filiform tips of the bracts: 

 outer akenes commonly corky-thickened and with broad truncate summit, 

 those toward the centre narrower and thinner-walled. — On the plains, from 

 the Saskatchewan to Texas and westward to the Sierra Nevada. 



Var. nuda, Gray. Rays wanting. — With the radiate form in Colorado 

 and New Mexico. 



* * Akenes narrow, excisely truncate or bidentate at summit : pappus awns 



mostly 2. 



2. G. nana, Nutt. Rather low and slender, 6 to 30 inches high, the 

 larger plants corymbosely and freely branched above : leaves thinnisb, lanceo 

 late and linear, or the lower spatulate, entire or spimiluse serrate : head:- 

 small : bracts of the involucre with slender and squarrose soon revolute tips, 

 as in the last : rays 1 6 to 30. — From N. W. Wyoming to Oregou and Wash- 

 ington ; replacing G. squarrosa in the Northwest, rthwest. 



8. CHEYSOPSIS, Nutt. Golden Aster. 



Herbs, with pubescence from hispid to silky, leaves entire or few-toothed, 

 yellow flowers in middle-sized heads terminating the stem and branches. 

 Our single species includes a multitude of forms, the more marked of which 

 are given as varieties. 



1. C. villosa, Nutt. A foot or two high : leaves from oblong to lanceo- 

 late, rarely few-toothed, usually cinereous or canescently strigose or hirsute 

 and sparsely hispid along the margins and midrib, an inch or two long : heads 

 mostly terminating leafy branches, sometimes rather clustered, naked at base 

 or leafy-bracteate : involucre campanulate, 4 or 5 lines high ; its bracts com- 

 monly strigulose-canescent, sometimes almost smooth, acute : akenes oblong- 

 obovate, villous: outer pappus of chaffy bristles . — On open ground from 

 the Saskatchewan to Alabama and westward across the continent. 



Var. hispida, Gray. Small and low, with hirsute and hispid pubescence, 

 not canescent : heads particularly small : involucre not canescent, sometimes 

 glabrous. — Proc. Acad. Philad. 1 863, 65. Saskatchewan to W. Texas and 

 Arizona. 



Var. diseoidea, Gray. Heads destitute of rays : involucre somewhat 

 canescent : otherwise nearly as the last. — Synopt. Fl. i. 123. Canons, W. Mon- 

 tana, Watson. 



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