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 truncate 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-pinnatifid : involucre strongly 

 squarrose 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. nan a, Nutt. Rather low and slender, 6 to 30 inches high, the 

 larger plants corymbosely and freely branched above : leaves thinnish, lanceo- 

 late and linear, or the lower spatulate, entire or spinulose serrate : heads 

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

 as in the last : rays 16 to 30. From N. W. Wyoming to Oregon and Wash- 

 ington Territory ; replacing G. squarrosa in the Northwest. 



8. CHRYSOPSIS, 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. 1863, 65. Saskatchewan to W. Texas and 

 Arizona. 



Var. discoidea, 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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