520 OOMPOSITiE. 



linear and entire, or laoiniate-pinnatifid. Flowers yellow, the heads 

 on slender peduncles. Eays 5 to 15, showy for the size of the heads, 

 or sometimes very short. Involucre campanulate or hemispherical, 

 its bracts as many as the rays, ovate or oblong and becoming more 

 or less carinate below the middle. Receptacle subulate-conical. 

 Achenes linear but somewhat broadened upward. Pappus of paleaj 

 or awns or both or none. (Dedicated to the Russian zoologist, Bser.) 



A. Pappus of one or more awns and several blunt palese, usually alternat- 

 ing, sometimes wholly wanting in the same species; pubescence soft- 

 hairy or none; at least some of the leaves pinnatifid or toothed. 



Insular species . . 1. B, maritima. 



Mainland species. 

 Plants slender. 

 Pappus-awns usually 4 . .... . 2. B. Fnmonti. 



PappuF-awns usually 2 Z. B. tenella. 



Plants stoutish; leaves broadly ligulate with few or several salient 

 linear lobes 4. J3. uliginosa. 



B. Pappus uniform, paleaceous; pubescence as in the last section; leaves 

 entire or pinnatifid. 



Involucre campanulate or hemispherical ; rays conspicuous. 



Leaves filiform and entire; salt marsh species . , 5. 5. carnosa. 



Some leaves pinnatifid; alkaline plains 6. .B. platycarpha. 



Involucres very narrowly cylindrical; rays so short that the heads are 

 seemingly rayless; leaves very narrow, entire . . . 7. B. Tnicroglossa. 



C. Pappus uniform, of awn-like palese or bristles; pubescence hirsutulous; 



leaves entire or often serrate in no. 10. 

 Annuals. 



Pappus none 8. £. chrysostoma. 



Pappus usually present. 



Pappus of awn-like bristles 9. B. gracilis. 



Pappus with the awns paleaceous at base 10. B. birsutula. 



Perennial; nearly simple; peduncles 4 to 8 In. long; pappus none or 

 present . . . . 11. iJ. macrantha. 



1. B. maritima Gray. Stoutish, branching, 3 or 4 in. high, 

 slightly villous, especially on the margins of the involucral bracts; 

 leaves linear or oblong-linear, entire or some sparingly toothed; rays 

 6 to 8, short and broad; pappus of 3 to 5 slender awns, with interven- 

 ing laoiniate paleas; achenes appressed-pubescent with short hairs. 



Farallone Islands. 



2. B. Fremonti (Benth.) Gray. Erect, slender, 7 to 13 in. high; 

 herbage nearly glabrous below, rather finely pubescent on the pedun- 

 cles and involucres, or the involucres nearly canescent; leaves narrowly 

 linear and entire, or mostly parted into linear lobes; involucre broad, 

 its bracts 10 to 12, broadly ovate; rays as many or fewer, with oval 

 ligules shorter than the width of the disk; pappus of about 4 slender 

 awns and as many or more numerous very small palese, or seldom 

 none. 



Plains from Solano Co. southward. Mar.-Apr. Involucres 

 nearly canescent. 



3. B. tenella (Nutt.) Gray. Erect, sparingly branching, 5 to 8 

 in. high, somewhat canescent; leaves linear and entire or some of the 

 lowest laciniate; rays 6 to 8, oval or oblong, little or not at all 

 exceeding the disk; palese and awns each usually 2 or often wanting. 



Plains of eastern Contra Costa Co. Apr.-May. 



