332 COMPOSITE. BaUa. 



Amauria, Benth. Bot. Sulph., of Lower California, insufficiently known, is per- 

 haps an epappose Bahia. 



1. Suffruticose (jB. ambrosioides, Lag., of Chili) or herbaceous from a per- 

 ennial sometimes lignescent root : palete of the pappus 4 to 8, obovate or spatu- 

 late, with rounded or truncate scarious summit, and thickened base or imperfect 

 costa : leaves dissected or cleft, the lower opposite. 



B. oppositifolia, NUTT A span or two high, fastigiately branched and many-stemmed, 

 herbaceous to the base, very leafy up to the short-peduncled heads, cinereous with fine close 

 pubescence : leaves mostly opposite, petioled, pnlmately or pedately 3-5-parted into linear 

 divisions little broader than the margined petiole : head 4 or 5 lines high : bracts of the 

 involucre oblong or oval, comparatively close (the outer obscurely carinate-one-nerved) : 

 rays 5 or 6, oval, hardly surpassing the disk-flowers : akeues slender, glandular : pappus half 

 the length of the corolla-tube, the paleaj narrowly obovate, witli strongly opaque centre eva- 

 nescent near the summit. Torr. & Gray, Fl. ii. 376; Gray, PI. Feudl. 99. Trichophi/ltum 

 oppositifoHum, Nutt. Gen. ii. 1G7. Sterile hills and plains, Nebraska to Colorado and the 

 borders of New Mexico. 



B. absintllifolia, BEXTH. About a foot high from an herbaceous root or harely suffru- 

 tescent base, diffusely branched, tomentulose-canescent, and with sparsely corymbose-panicu- 

 late heads on slender peduncles : leaves opposite and the upper alternate, pedately or 

 sometimes pinnately 3-5-parted into narrowly linear or lanceolate divisions and lobes : 

 involucre more lax ; its bracts oblong-spatulate or lanceolate with narrowed base : rays 9 to 

 12, lanceolate-oblong, much exceeding the disk: akenes slender, pubescent : pappus nearly 

 equalling the proper corolla-tube, its paleas more dilated and broadly thiu-scarious above. 

 PI. Hartw. 18. Arizona, near Tucson, Palmer, Lemmon. (Forms almost as slender and 

 narrow-leaved as the plant of Northern Mexico.) 



Var. clealbata, GRAY. Perhaps more lignescent at base, more whitened with fine 

 pannose tomeutum: leaves less divided, commonly only 3-cleft into lanceolate or linear- 

 oblong lobes, or some lower ones oblong-lanceolate and entire. PI. Wright, i. 121 ; Proc. 

 Am. Acad. xix. 27. B. dealbata, Gray, PI. Feudl. 99. Dry plains, W. Texas to Arizona. 

 (Adj. Mex.) 



2. Herbaceous from a perennial caudex : leaves all alternate and entire, 

 coriaceous: palete of the pappus about 10, linear-lanceolate, and with a distinct 

 excurrent or percurrent costa. Plafyschkuhria, Gray. 



B. nudicaulis, GRAY. Cinereous-puberuleut and glabrate, upper part of the srapifortn 

 stem and involucre minutely glandular, a 'span or two high : leaves nearly all radiml, oval or 

 spatulate-oblong (an inch or more long), tapering into a slender petiole : heads solitary or 

 few and somewhat corymbosely paniculate, nearly half-inch high: involucre hemispherical, 

 of about 10 oblong bracts: rays 6 to 9, oblong : pappus fully half the length of the cuneate- 

 linear sparsely hairy akene ; the thin margins of the palere of the pappus erose, and the 

 short-excurrent awn barbellate-hispidulous. Proc. Am. Acad. xix. 27. Schkuhria (Platy- 

 schkuhria) integrifolia, Gray in Am. Nat. viii. 213, & Proc. Am. Acad. ix. 198, excl. var. 

 Wind River Mountains, N. W. Wyoming, Parry. 



B. oblongifolia, GRAY, 1. c. Smaller : stems sparsely leafy almost to the 3-cephalous 

 naked inflorescence : leaves narrowly oblong : head only 4 lines high, narrow : palea; of the 

 pappus firmer, smoother, and with entire edges, little shorter than the glabrate akene. 

 Schkuhria integrifolia, var. oblongifolia, Gray in Am. Nat. 1. c. On the San Juan and Rio 

 Colorado, near their junction, S. E. Utah or adjacent Colorado, Newberry, Brandegee. 



3. Annuals, with once or twice palmately or pedately divided leaves : akenes 

 mostly hirsute along the slender attenuate base, at least on the angles. Achyro- 

 pappus, PIBK. 



* Leaves mainly opposite, at least all the lower ones, their divisions narrowly linear: pappus of 

 broad and very obtuse pale;e, scarious above, callous-thickened and opaque at base, as in 1 : 

 ray-flowers occasionally wanting. Gray, Proc. Am. Acad. xix. 27. Achyropqppus, HBK., DC. 



