SUNFLOWER FAMILY. 



535 



Pappus of disk and ray unlike 1. B. plumosa. 



Fappus of disk and ray similar 2. B. laxa. 



1. B. plumosa (Kell.) Greene. Two to 3 ft. high, copiously beset 

 above with tack-shaped glands; leaves on the branchlets small and 

 bract-like; heads 15 to 20-flowered, racemosely disposed on the 

 branches; bracts of the involucre short and very glandular; ray- 

 achenes with a minute crown of short scales; disk-achenes with nearly 

 erect plumose bristles as long as the achene. — (Hemitonia plumosa 

 Gray.) 



Antioch and Stockton. 



2. B. laxa Greene. Three to (5 ft. high; heads larger, borne singly 

 at the ends of the branches, 20 to 25-flowered; pappus of disk-achenes 

 short and spreading, less plumose than in the preceding, only * as 

 long as the achene; ray-achenes similar. — (Hemizonia plumosa var. 

 subplumosa Gray.) 



Stockton to Stanislaus Co. Perhaps not specifically distinct from 

 the preceding. 



52. BLEPHARIPAPPUS Hook. Layia. 



Vernal annuals with alternate leaves (or the lowest opposite in one 

 species) and usually showy heads of flowers terminating the branches. 

 Disk-corollas yellow. Ray-flowers 8 to 20, yellow, white, or yellow 

 tipped with white. Bracts herbaceous, the thin margins at base 

 enfolding the achene and usually deciduous with it. Receptacle broad 

 and flat, with a row of thin bracts between ray- and disk-flowers, and 

 sometimes with additional ones among the disk-flowers. Ray-achenes 

 flattened, without pappus, almost always glabrous. Disk-achenes 

 commonly pubescent, with a pappus of 5 to 20 palea? or bristles or 

 rarely none. (Greek blepharis, eye-lash, and pappos, the modified 

 calyx being likened to the fringe of hairs on an eye-lid.) 



We have here in this West American genus series of forms simu- 

 lating each other exactly in habit, foliage, and heads of flowers, 

 differing only in technical character of the pappus or color of the 

 ray. This situation is paralleled in Cryptanthe of the Borraginacea? 

 and in other genera. The acquisition of more abundant material and 

 of field notes will be valuable aids to a more satisfying study of the 

 forms here tentatively listed. 



A. Pappus-bristles hairy or long-plumose below. 



Bracts of the involucre hirsute or hispid (the basal margin where folded 

 around the achene not denticulate-ciliate). 

 Inner hairs of pappus-bristles woolly and interlaced. 

 Rays white and 



Inconspicuous; leaves all entire I. B. hispidus. 



Showy; lower leaves incised or toothed 2. B. glandulosus. 



Rays yellow (rarely white-edged) 3. B. elegans. 



Hairs of pappus-bristles straight (no woolly inner ones). 

 Rays wholly white. 

 Rays conspicuous, much exceeding the disk; interior plains: var. 



heterotrich us of 2. B. glandulosus. 



Rays inconspicuous, scarcely exceeding the disk; seashore 



4. B. carnosus. 



