194 
30. ASTER L. (STARWORT. ASTER.) 
Mostly perennial herbs, with corymbed, panicled, or racemose heads, 
white, purple or blue fertile rays and yellow disk often changing to pur- 
ple, many-flowered heads, involucral bracts more or less imbricated and 
usually with herbaceous or leaf-like tips, flat receptacle, more or less 
flattened achenes, and a (usually) simple pappus of capillary bristles. 
fod 
§1. MEGALASTRUM, Head very large (2.5 em. in diameter exclusive of the large and 
numerous rays): involucral bracts imbricated in two or three unequal series, some- 
what herbaceous: achenes 2 to 4-nerved: pappus-bristles unusually coarse and rigid 
(white in ours). 
1. A. Wrightii Gray. Viscous-pubescent, 3 dm. or more high: leaves oblong-spat- 
ulate, setiferous-mucronate, entire, or with one or two teeth, 3.5 em. long including 
the margined petiole: heads pedunculate and solitary, terminating rigid branches: 
involucral bracts ovate-lanceolate or the inner narrower, rather lax, viscid, the cau- 
date-acuminate tips surpassing the disk: rays purple, narrowly oblong, 30 to 40, 16 
to 18 mm. long: pappus of unequal strongly denticulate bristles, the larger almost 
aristiform. (Townsendia Wrightii Gray.)—Rocks and stony hills on the Rio Grande in 
southwestern Texas. 
§2. Ha.eastruM. Heads smaller: involucral bracts rigid, more or less leafy, nearly 
equal: achenes 8 to 10-nerved: pappus simple, coarseand rigid, the stronger bris- 
tles somewhat clavate, ferruginous or tawny. 
2. A. paludosus Ait. Glabrous or nearly so: stems 3 dm. high: leaves linear, 
entire: heads 12 mm. high, rather few, racemose or spicate: outer involucral bracts 
lax, leafy: rays purple.—Wet pine barrens, extending into Texas from the Gulf 
States. 
§ 3. ASTER proper. Jnvolucral bracts imbricated in various degrees, with herbaceous or 
leaf-like summits, or the outer entirely foliaceous: rays numerous: pappus simple, 
soft and nearly uniform: achenes flattened. 
* Involucre and usually the branchlets viscidly or pruinose-glandular, well-imbricated or 
loose: pubescence not silky: leaves entire (or the lower with few teeth), the cauline all 
sessile or clasping: rays showy, violet to purple. 
3. A. Fendleri Gray. Rigid, 3 dm.high or less: leaves firm, linear, 1-nerved, 
hispid-ciliate, 2.5 cm. long or mostly much less: heads scattered, 6mm. high: invo- 
lucral bracts linear-oblong, obtuse or the inner acute, not squarrose.—Plains and 
sand-hills of northwestern Texas. 
4. A. oblongifolius Nutt. Minutely glandular-puberulent, much branched above, 
rigid, paniculate-corymbose, 3 to 6 dm. high: leaves narrowly oblong or lanceolate, 
mucronate-pointed, partly clasping, thickish, 2.5 to 5 cm.long by 4 to 10 mm. wide: 
involucral bracts nearly equal, broadly linear, spreading above, appressed at base: 
rays violet-purple: achenes canescent.—Rocky banks and bluffs, extending into 
Texas from the Atlantic States. Extending to the western borders of Texas, in 
drier and more exposed places, is var. RIGIDULUS Gray, alow form, with more rigid 
and hispidulous scabrous leaves. 
* * Leaves whitened, silvery-silky both sides, all sessile and entire, mucronulate : involucre 
imbricated in 3 to several rows: rays showy, purple-violet. 
5. A. sericeus Vent. Stems slender, branched: leaves silver-white, lanceolate 
or oblong: heads mostly solitary, large, with 20 to 30 rays, terminating the short 
branchlets: bracts of the globular involucre similar to the leaves, spreading except 
the short coriaceous base: achenes smooth, many-ribbed.—Prairies and dry banks, 
extending into Texas from the Mississippi States. 
6. A. phyllolepis Torr. & Gray. Moreslender and with long simple branches, 
Merely canegcent; leaves small; lower cauline 2.5 cm. long or more, oblong; those 
