20-1 COMPOSITE. (COMPOSITE FAMILY.) 



1. P. sagittata, Gray. Leaves from deltoid-oblong to reniform-hastate, 

 from acute to rounded-obtuse, repand-dentate, very white-tomentose beneath, 

 when full grown 7 to 10 inches long : heads short-racemose becoming corym- 

 bose. Bot. Calif, i 407. Wet ground, in the mountains of Colorado and 

 northward ; across the continent in northern latitudes. 



67. HAPLOESTHES, Gray. 



The name refers to the few (4 or 5) bracts of the involucre. 



1. H. Greggii, Gray. Somewhat fleshy, herbaceous or suffrutescent, a 

 foot or two high, fastigiately branched, glabrous, leafy up to the loose cymes 

 of a few slender-pedunculate naked heads : leaves all opposite, very narrowly 

 linear or filiform, entire ; the lower connate at base : heads 2 or 3 lines high : 

 flowers yellow : ligules 1 or 2 lines long. PI. Feudl. 109. Saline soil, S. E. 

 Colorado to W. Texas. 



68. TETRADYMIA, DC. 



Low and rigid shrubs, sometimes spinescent, canescently tomentose ; with 

 alternate and sometimes fascicled narrow and entire leaves, cymose or clus- 

 tered heads of yellow flowers, and a copious white pappus. 



* Involucre 4-flowered, of 4 or 5 bracts: pappus extremely copious: akenes either 



very villous or glabrous : under shrubs, afoot or two high. 



1. T. canescens, DC. Permanently canescent with a dense close tomentum, 

 unarmed, fastigiately branched : leaves from narrowly linear to spatulate-lanceo- 

 latc, an inch or less long : heads | to inch long, most of them short-pedun- 

 culate. Hills and plains, N. Wyoming and British Columbia to New Mexico, 

 Arizona, and California. 



Var. inermis, Gray. A form with shorter and crowded branches, shorter 

 leaves more inclined to spatulate and lanceolate, and smaller heads. Bot. 

 Calif, i. 408. The commonest form. 



2. T. glabrata, Gray. Whitened with looser at length deciduous tomentum, 

 unarmed: branches more slender, spreading: leaves at length naked and 

 green, primary ones slender-subulate, cuspidate, on young shoots appressed, half- 

 inch long ; those of fascicles in their axils spatulate-linear, fleshy, pointless : 

 heads mostly short-pedunculate : involucre often glabrate. Pacif. R. Rep. ii. 

 122. From Colorado and Utah to California and Oregon. 



3. T. Nuttallii, Torr. & Gray. Pubescence and foliage of T. canescens, 

 var. inermis, bearing rigid divergent spines in place of primary leaves : leaves of 

 the axillary fascicles mostly spatulate: heads more glomerate. Fl. ii. 447. 

 Utah and Wyoming. 



* * Involucre 5 to 9-flowered, of 5 or 6 broader bracts : proper pappus less copi- 



ous, reduced nearly or quite to a single series of bristles, which are covered by a 

 false pappus of extremely long very soft and white woolly hairs which densely 

 clothe the akene: shrubs 2 to 4 feet high, at least the branches densely white- 

 tomentose. 



4. T. spinosa, Hook. & Arn. Branches divaricate, rigid, bearing rigid 

 and straight or recurved spines in place of primary leaves : secondary leaves 



