227 
* Pappus of about 20 unequal rigid bristles: rays none: disk-flowers 12 to 15: leaves 
mostly opposite, as broad as long, abruptly slender-petioled. 
1. L. rupestris Gray. Pubescent, slightly viscid, leafy to summit: leaves 12 mm. 
long, sometimes crenately sometimes strongly and acutely dentate or almost lacini- 
ate: pappus much exceeding short proper tube of corolla.—Southwestern Texas. 
2. L. cinerea Gray. Tomentose-canescent: leaves more orbicular, almost entire: 
pappus hardly surpassing proper tube of corolla, which is more than half as long as 
the short-cylindraceous throat: achenes sometimes 4-nerved.—Rocks along Escon- 
dido creek, southwestern Texas (Bigelow). 
** Pappus a solitary very slender bristle or none: disk-flowers 15 to 20: heads commonly 
cymose and pedunculate. 
3. L. halimifoliaGray. Stems crowded ona thick woody caudex: leaves coriaceous, 
resinous-punctate or atomiferous, somewhat viscid, broadly ovate or rhombic, sel- 
dom 2.5 cm, long, laciniately dentate, abruptly long-petioled: rays 4 to 6, with broad 
and short ligules little longer than the tube: pappus none.—Southwestern Texas. 
4. L. angustifolia Gray. Leaves lanceolate or rhombic-lanceolate, tapering into 
margined petioles, laciniately 1 to 5-toothed or lobed: heads less numerous, scat- 
tered: rays none: otherwise much like the last.—Southwestern Texas, on high and 
rocky hills of the Pecos and Rio Grande. 
5. L. Lindheimeri Gray. Stems from a thick woody base: leaves thinner, oblong 
or ovate, glabrous, few-toothed or some entire, contracted at base into a short petiole: 
heads loosely cymose: rays 3 to 6, very short, sometimes none: pappus a single slen- 
der bristle equaling the proper tube of the corolla.—Rocky banks of the Guadalupe, 
near New Braunfels (Lindheimer). 
*** Pappus a pair of stouter naked bristles, one from each angle of the achene: head 
only 6 to 8-flowered. 
6. L. bisetosa Torr. Hispidulous-puberulent, minutely resinous-atomiferous and 
punctate: stems 2.5 to 7.5 cm. high: leaves mostly alternate, coriaceous, spatulate- 
ovate, obscurely few-toothed: heads solitary and sessile: rays none: involucral bracts 
broadly linear, carinate-concave at base: achenes puberulent, rather longer than the 
rigid awns.—In a cafion on the Rio Grande, below Presidio del Norte (Parry). 
82. PERITYLE Benth. 
Mostly annuals, with petiolate dentate or palmately-lobed leaves 
(lower opposite, upper alternate), small or middle-sized pedunculate 
heads terminating the branches, yellow or white rays (when present), 
4-toothed disk-corollas, narrow and distinct involucral bracts, flat carti- 
laginous-margined usually strongly ciliate achenes, and pappus a scaly 
or cupulate crown and commonly a slender awn from one or both angles, 
* Crown of the pappus an entire or undulate firm and shallow border: achene hardly cili- 
ate: suffruticulose. 
1. P. dissecta Gray. Dwarf, 7.5 to 10 cm. high, cinereous-pubescent, very leafy : 
leaf-blades equaled by petiole, round-cordate in outline, pedately cleft and parted 
and dissected into short linear lobes: heads subsessile, 6 to 8mm. high: rays none: 
achenes minutely cinereous-hirsute, a short scabrous awn from one angle (or this 
wanting). (Laphamia dissecta Torr. Pl. Wright.)—Rocks at Presidio del Norte. 
_** Pappus rather a conspicuous crown of scales and one long and delicate awn: achenes 
densely ciliate with long beard: herbaceous. 
+ Rays 4 to 6 mm. long, deep yellow: disk-corollas funnelform, 
2. P. Vaseyi Coulter. Minutely glandular pubescent: leaves 3.5 to 6.5 em. long, 
with broad outline, palmately or pinnately divided into 3 long-stalked broadly cuneate 
18430—No, 2 6 
