GENuS 98. THISTLE FAMILY. 535 
98. HAPLOESTHES A. ‘Gray, Mem. Am. Acad. (II) 4: 109. 1849. 
Perennial caulescent, partly woody and partly fleshy plants, with opposite narrow entire 
leaves, the lower connate-sheathing, and corymbose heterogamous radiate heads. Invo- 
lucre of few broad many-nerved bracts. Receptacle flat or slightly convex, naked. Ray- 
flowers pistillate, fertile, the rays yellow, spreading or recurved. Disk-flowers perfect, fertile. 
Anthers obtuse and entire at the base. Style-branches of the disk-flowers capitate-truncate. 
Achenes narrow, 10-ribbed. Pappus of 1 series of slender scabrous bristles. [Greek, simple 
garment, the involucre composed of few bracts.] 
A monotypic genus of the south-central United States and Mexico. 
1. Haploesthes Greggii A. Gray. Gregg’s 
Haploesthes. Fig. 4604. 
Haploesthes Greggii A. Gray, Mem. Am. Acad. (II) 
4: 109. 1849. 
Stems usually branched at the base, the branches 
1°-2° tall, glabrous, striate, corymbose above. 
Leaves fleshy, the lower ones connate and sheath- 
ing the stem, narrowly linear or linear-filiform, 
’-2' long, entire; heads short-peduncled, few to- 
gether in cymes; involucres 14’’-2” high, the bracts 
oval to orbicular, rounded at the apex, thin-mar- 
gined; rays yellow, 1”-2” long; achenes 1” long. 
In saline and gypsum soil, Kansas and southern 
Colorado to Texas and Mexico. April—Sept. 
99. ERECHTITES Raf. Fl. Ludov. 65. 1817. 
Erect, usually branching herbs, with alternate leaves, and (in our species) rather large 
discoid many-flowered heads of whitish flowers, corymbose-paniculate at the ends of the 
stem and branches. Involucre cylindric, swollen at the base, its principal bracts in I series, 
linear, with or without some much smaller outer ones. Receptacle concave, naked. Marginal 
flowers in 2-several series, pistillate, fertile, their corollas filiform, the limb 2-4-toothed. 
Central flowers perfect, fertile; corolla narrowly tubular, the limb 4-5-toothed, the style- 
branches elongated, truncate or obtuse at the summit. Anthers obtuse and entire at the base. 
Achenes linear-oblong, angled or striate. Pappus of copious capillary soft smooth white 
bristles. [Ancient name of some groundsel.] 
About 12 species, natives of America and Australasia. The following typical one is the only 
species known to occur in North America: 
