BLEPHARAPAPPUS COMPOSITE 345 



wanting), each subtended by a bract of the usually unixerial involu- 

 cre which partly or completely encloses its achene. Dish" flowers 

 hermaphrodite, but mostly some or all of them sterile. Receptacle 

 chaffy throughout or of only a more or less united ring between the 

 ray- and disk-flowers. 



* Scales of the receptacle distinct, chaffy-membranaceous or scari- 

 ous, mostly deciduous with the fruit. Bracts of the involucre merely 

 concave. 



46 BLEPHARIPAPPUS Hooker. Fl. i, 316 in part. 

 Low corymbosely or paniculately branched annuals with 

 narrow alternate leaves and rather small heads of white or purplish 

 flowers, Heads heterogamous. with 3-6 pistillate broad-cuneilorm 

 3-lobed ray- and 6-12 perfect 5-toothed disk-flowers, or some of 

 the central ones sterile. Bracts of the involucre nearly in a 

 single series, nearly flat and almost equal. Receptacle convex, 

 chaffy throughout, the chaff thin and membranaceons, deciduous 

 with the fruit. Style in the disk-flowers long, thickened upward, 

 hairy, 2"cleft only at the apex, the branches obtuse and not 

 appendaged, or in the central sterile ones nearly entire Achenes 

 turbinate, silky-villous. Pappus of 10-12 linear or aristiform 

 palese with hyaline margins which are mostly laeerate-fimbriate 

 so as to appear plumose. 



B> scaber Hook. 1. c. Puberulent and scabrous, and with some hispid 

 hairs above: stem stoutish, 4-12 inches high, loosely branched : leaves 

 linear, sessile, )^-2 inches long with entire revolute or involute margins : 

 heads short-pednneled, terminating the paniculate branches : bracts of the 

 involucre lanceolate, acute, 4-5 lines long, more or less hirsute : rays much 

 exceeding the involucre, deeply 3-lobed, always inrolling and becoming 

 inconspicuous when the sun shines on them : anthers brownish-purple. 

 Dry plains and mountains, Brit. Columbia to California and Idaho, east 

 of the Cascade Mountains. 



B. laevis Gray Bot. Gaz. xiii, 73. Stem slender, 6-12 indies high, 

 smooth, branched: leaves linear, 5-10 lines long, sessile, the lower ones 

 spreading, those of the branches closely appressed : heads small, termina- 

 ting the filiform branchlets: bracts of the involucre linear-lanceolate, 2-3 

 lines long, scabrous : rays 3-4 lines long, not closing in sunshine, deeply 

 3-lobed, often with dark-purple veins. On dry plains and hillsides, 

 southern Oregon to California. 



* * Scales of the receptacle always present betweent the ray- and 

 disk-flowers, usually more or less united into a cup. Bracts of the 

 involucre conduplicate-infolded and embracing the laterally com- 

 pressed achenes. 



47 ANISOCAEPHUS Nutt. Trans. Am. Phil. Soc. vii, 388. 



Villous-hirsute perennial herbs with linear to lanceolate entire 

 or denticulate sessile leaves and numerous paniculate or corymbose 

 heads of flowers with yellow, rays that do not close in sunshine. 

 Heads many-flowered; the ray-flowers about twelve, ligulate, 

 pistillate, those of the disk tubular, staminate and pistillate but 



