154 BOTANY. 



divided, tapering into a petiole ; divisions linear or oblong, or sometimes 

 the upper leaves entire, sessile; stems branching toward the summit, a 

 single head terminating each branch ; scales of the involucre in about three 

 series, linear, acute, and with scarious margins ; rays white, in about two series, 

 fertile; disk-flowers perfect, in both the short coroniform pappus distinctly 

 marked, with a few longer bristles intermixed ; achenium with a distinct 

 epigynous disk, somewhat flattened (sometimes with distinct marginal and 

 facial ribs, as in Mathceranthera). — Mount Graham, Arizona, at 9,000 feet 

 altitude (731). Number 500, from Camp Bowie, Ariz., appears to be the 

 canescently hirsute variety alluded to in Botany of Mexican Boundary, p. 

 78. In my specimen, the leaves are also much more, finely divided toward 

 the summit (to say nothing of some difference in the achenia) than in the 

 typical form. I think this might be safely regarded as a distinct species. 



Erigeeon pumilum, Nutt. — Denver, Colo. (514). 



Eeioeron maceanthum, Nutt. — Mount Graham, Arizona, at 9,000 feet 

 altitude (736) ; also from Utah. 



Eeigeeon Coulteri, Porter. — In absence of sufficient material, I am 

 obliged to quote the following good description of Professor Porter (Fl. 

 Colorado, p. 61) : " Stem simple, from a slender root, 6-12' high, bearing a 

 single head, smooth below, pilose-pubescent above, leafy to the top; leaves 

 thinnish, pubescent, with ciliate margins, all more or less serrate-denticu- 

 late, mucronate, erect, gradually diminishing in size upward; lower ones 

 oblong-spatulate or elliptical, tapering into a margined, ciliate petiole, 

 upper ones oblong or lanceolate, acute or acuminate, sessile, and partly 

 clasping; head large 1-2' broad, including the numercras white rays ; in- 

 volucre about 9" broad, hemispherical, densely pilose, but scarcely woolly; 

 scales lance-linear, with scarious margins, tips elongated, subulate, spread- 

 ing, glandular ; achenia pubescent ; bristles of the pappus minutely 

 scabrous, outer ones short and few; alveoli of the receptacle rough with 

 lacerate margins." In my specimen, the plant is almost glabrous through- 

 out, except the scales of the involucre, and the leaves are barely denticulate ; 

 flower also was purplish. In my preliminary report, I published this (519) 

 as "E. macranthum verging toward grandiflorum". — Union Creek Pass, 

 Colorado, at 11,300 feet altitude. 



