CARDUACEAE 1187 
1. Isocoma Drummóndii (T. & G.) Greene. Stems branched at the base, 2-3 dm. 
tall, corymbose above. Leaves numerous; blades linear or slightly broadened upward, 2-5 
cm. long, entire or nearly so: heads rather conspicuous: involucres campanulate or tur- 
binate-campanulate, 8-9 mm. high ; bracts narrowly oblong to linear, acute or acutish, 
with green viscid tips: achenes about 3 mm. long. 
In the lower Rio Grande valley and on the coast of Texas. Spring. 
2. Isocoma coronopifólia (A. Gray) Greene. Stems 2-6 dm. tall, freely branching 
and corymbose above. Leaves numerous ; blades 1-3 cm. long, pinnately parted, the seg- 
ments 3-9, about as broad as the rachis: heads clustered, at the ends of short peduncles : 
involueres campanulate, 5-6 mm. high ; bracts oblong, linear-oblong or slightly broadened 
upward, obtuse : achenes about 2 mm. long. 
On plains, Texas. Spring and summer. 
32. ISOPAPPUS T. & G. 
Annual or biennial caulescent herbs, with rough-pubescent foliage. Leaves alternate : 
blades narrow, often coarsely and remotely toothed, 1-nerved. Heads radiate, paniculate, 
peduncled. Involucres many-flowered : bracts narrow, in 2-3 series. Receptacle pitted. 
Ray-flowers 5-12, pistillate. Disk-flowers 7-20, perfect: corollas yellow. Stigmas narrow, 
pubescent. Achenes terete, broadened upward, pubescent. Pappus a single series of rough 
nearly equal hair-like bristles. 
Peduncles glandular: bracts of the involucres glandular: ray-flowers 5-8: disk-flowers 7-14. 
1. I. divaricatus. 
Peduncles pubescent: bracts of the involucres glabrous: ray-flowers 10-12: disk-flowers 18-20. 
2. I. Hookerianus. 
1. Isopappus divaricàtus (Nutt.) T. & G. Stems 3-12 dm. tall, hispid and more or 
less glandular. Leaf-blades linear-oblanceolate to narrowly linear, 2-10 cm. long, acute or 
acuminate, remotely but sharply toothed, or entire near the top of the stem, copiously 
ciliate: heads often numerous: involucres oblong-campanulate, 6-6.5 mm. high ; bracts 
linear-lanceolate to linear, acuminate, glandular-pubescent: ray-flowers with oblong or 
elliptic-oblong ligules : achenes 2 mm. long, pubescent. 
In dry soil, South Carolina and Kansas, south to Florida and Texas, Summer and fall. 
2. Isopappus Hookeriànus T. & G. Stems 3-5 dm. tall, sparingly rough-pubescent. 
Leaf-blades narrowly linear, sometimes broadest below or above the middle, 2-6 cm. long, 
acuminate, ciliate near the base, serrulate above the middle, prominently nerved beneath : 
heads few: involucres campanulate, 5-6 mm. high; bracts linear-subulate, glabrous or 
nearly so, firm, sharp-pointed. 
On prairies, Texas. Summer. 
33. MAUCHIA Kuntze. 
Annual caulescent branching herbs. Leaves alternate: blades narrow, entire. Heads 
radiate. Involucres campanulate, relatively small: bracts thin, scarious-margined, ap- 
pressed, abruptly acuminate.  Ray-flowers fruit producing, often 12, with short styles. 
Disk-flowers not fruit producing, about 12, the stigmas filiform. Receptacle flat. Anthers 
obtuse at the base. Achenes various, those of the ray perfect, thickened upward, 3-angled, 
with a rib at each angle, and pappus of unequal hair-like bristles about as long as the 
achene; those of the disk abortive, their pappus usually of 2 bristles, somewhat chaffy, 
dilated at the base. [Bradburya T. & G., not Raf.] 
1. Mauchia hirtélla (T. & G.) Kuntze. Foliagehispid. Stems 2-5 dm. tall, slender: 
leaves various, 1-4 cm. long, those of the basal and lower stem-leaves with narrowly 
spatulate blades ; upper stem-leaves with blades varying from linear-spatulate to linear-fili- 
form : heads solitary at the ends of slender branches: involucres 7-9 mm. high ; bracts 
chaffy, oblong-lanceolate to linear, acuminate, glabrous except the midrib: ligules of the 
ray-flowers yellow, 6-8 mm. long: achenes 3 mm. long, strigillose. à 
On prairies, Texas. Summer. 
34. STANFIELDIA Small. 
Branching caulescent herbs. Leaves alternate, relatively few: blades narrow, rather 
thick. Heads conspicuous, many-flowered, terminating stout peduncles which are enlarged 
at the top. Involucre of 3-4 series of loosely imbricated leathery striate-ribbed thin-mar- 
gined bracts. Disk yellow. Stigmas scarcely flattened, with ovoid appendages. Achenes 
10-ribbed, the ribs slightly pubescent. Pappus of sordid scabrous bristles. 
