436 COMPOSITE. Lygodemia, 



L. juncea, var. dianthopsis, Eaton, Bot. King Exp. 200, the well-developed and taller form, 

 leafy to the top. Erythremia grandiflora, Nutt. Trans. Am. Phil. Soc. vii. 445, dwarf form. 



— Gravelly hills or slopes, W. Wyoming (first coll. by Nuttall), Utah about Salt Lake (first 

 coll. by Stansbury), and S. Utah. 



L.'aph^lla, DC. 1. c. Stems mostly solitary from the root, slender and quite rush-like, 

 2 feet or so high, naked or nearly so, once or twice forked above, and bearing solitary long- 

 peduncled heads : leaves rather fleshy, chiefly radical or near the ground, filiform, elongated, 

 entire, or with one or two rare teeth ; upper reduced to minute scales at the forks : involucre 

 (mostly 10-flowered) and rose-colored ligules each two-thirds to three-fourths inch long. — 

 Torr. & Gray, 1. c. ; Chapm. Fl. 251. Prenanthes aphylla, Nutt. Gen. ii. 123 ; Ell. Sk. ii. 261. 

 Erythremia aphylla, Nutt. Trans. Am. Phil. Soc. 1. c. 446. — Dry pine barrens, S. Georgia 

 and Florida ; first coll. by Baldwin. 



Var. Texana, Toer. & Gray, 1. c. Stouter : leaves more numerous, from filiform 

 and usually with 2 or 3 lateral lobes to linear (2 lines broad) and sparingly pinnately lobed, 

 also some smaller leaves on the stem : some Texan specimens nearly like those of Florida. 



— Eocky hills and plains, Texas ; first coll. by Berlandier, Drummond, &c. 



§ 2. Diffuse and spinescent perennial, with flexuous branches not striate-angled : 

 pappus rigidulous, whitish, of unequal bristles. — § Pleiacanthus, Nutt. 



L. spinosa, Nutt. 1. c. Stems slender and rigid, low, much branched from an indurated 

 and matted- woolly base, otherwise glabrous : branchlets divergent, spinescent, bearing 

 minute scales in place of leaves and lateral very short-peduncled heads : lower cauline leaves 

 linear, entire, thickish, above soon reduced to scales : involucre 3-5-flowered ; its proper bracts 

 not more numerous, rather loose, lanceolate ; the unequal and more imbricated calyculate 

 ones comparatively broad and large : akenes much shorter than the pappus, not at all nar- 

 rowed upward, 4-5-costate. — Torr. & Gray, 1. c. ; Eaton, Bot. King Exp. 200 ; Gray, Bot. 

 Calif. 441. — Gravelly hills and plains in the arid district, S. Idaho to S. Nevada and the east- 

 ern borders of California ; first coll. by Nuttall. 



§ 3. Paniculately branched annuals, not spinescent : pappus white and soft. 



L. rostrata, Gray. Stem erect, 1 to 3 feet high, striate, leafy, corymbose-paniculate : leaves 

 narrowly linear, attenuate to both ends, entire, obscurely 3-nerved; cauline 3 to 7 inches 

 long, barely 2 lines wide ; uppermost slender-subulate : heads numerous, on scaly-bracteolate 

 erect peduncles : involucre over half-inch high, 8-9-flowered, of as many very narrowly linear 

 bracts and a few short calyculate ones : rays small and narrow, probably purplish : akenes 

 slender-fusiform, 4 or 5 lines long, distinctly attenuate at summit but not truly rostrate, 5-8- 

 striate, longer than the soft rather dull-white pappus. — Proc. Am. Acad. ix. 217. L. juncea, 

 var. rostrata, Gray, Proc. Acad. Philad. 1863, 69. — Plains along the eastern base of the 

 Rocky Mountains, from the Saskatchewan (Cypress Hills, Macoun) to Wyoming and Colo- 

 rado, where first coll. by Hall & Harbour. 



L. exigua, Guay, 1. c. A span or two high, effusely paniculate from the base, bearing 

 numerous small heads terminating short-filiform divergent branchlets or peduncles : branches 

 not striate : radical leaves spatulate or oblong (about inch long), from nearly entire to run- 

 cinate-pinnatifid ; cauline small and entire, soon reduced to minute bracts : involucre oblong, 

 2 lines high, 4-5-flowered, of as many narrowly oblong bracts and one or two very small 

 calyculate ones : akenes not 2 lines long, gradually tapering from the truncate summit to 

 base, broadly 4-5-costate, or rather narrowly 4-5-sulcate, somewhat longer than the bright 

 white pappus. — Prenanthes exigua, Gray, PI. Wright, ii. 105. — Stony hills, S. E. New 

 Mexico, Wright. S. W. Utah, Parry, Palmer. Mohave Desert, S. E. California, Parish. 



230. TR6XIMON", Nutt. (Probably from rpaya, T P w£ofiai, to chew, of 

 no obvious application to this, or to the factitious genus, partly Krigia, partly 

 Scorzonera, for which Gsertner coined the name.) — N. American with one or 

 two S. American herbs, acaulescent or nearly so, with a cluster of sessHe or sub- 

 sessile radical leaves, and simple scapes bearing a head of yellow or rarely purple 

 flowers, in summer. Occasionally in one species some chaffy bracts among the 



