SYNOPSIS OF THE FLORA" 't>JP ^COH&R^DO'."- : 69 



strigose-hispid above, younger ones silky-hirsute beneath ; peduncles 

 elongated, .bearing single heads; rays 10, oval-oblong, emarginate or 

 2-3 toothed, white, thrice the length of the ovate and hairy exterior 

 scales of the involucre, the inner inclosing the achenia, tuberculate- 

 scabrous toward the base, dilated above into a short, smooth hood, trun- 

 cate at the summit with the margin entire and involute. Purgatory 

 Paver, Dr. Bdl Xear Canon City, Redjield. 



IVA AXILLARIS, Pursh. Stem 6'-15' higli, much branched from a 

 somewhat slender, woody base, very leafy; leaves 9"-15" long, 3"-8" 

 wide, obovate or oblong, obtuse, narrowed at the bas*e, minutely ap- 

 pressed- pubescent, sessile; heads solitary in the axils of the leaves on 

 short, recurved pedicels ; scales of the campanulate involucre 4-5, dis- 

 tinct or united to the middle ; fertile flowers 4-5 ; chaff of the receptacle 

 filiform-linear. JTaM d; Harbour, 261. 



IVA CILIATA, Willd. Hall cfc Harbour, 262. 



IVA (BUPHROSYNE) XANTHUFOLIA, Gr.Hall tO Harbour, 263. Den- 

 ver, Dr. Smith. 



AMBROSIA TRIFIDA, L. Plains around Denver, Coulter. 



AMBROSIA PSILOSTACHYA, DC. On the Platte, near Denver, Dr. 

 Smith. 



FRANSERIA l TOMEXTOSA, Gr., PL FendL, p. 80. Herbaceous, pubes- 

 cent throughout, with a soft, silky, and silvery pubescence ; stem erect, 

 about 1 high, paniculate, bearing numerous panicled branches; leaves 

 pinnately 3-5 parted, very white, especially beneath, decurrent into a 

 short, narrowly-margined petiole; lowest apparently bipinnatifid, lobes 

 of the upper ones oblong or lanceolate, dentate or very entire except 

 the large 3-lobed terminal one; sterile involucres 3" in diameter 

 crowded in a dense raceme, 6-toothed, 18-20 flowered, fertile involucres 

 J the size, clustered in the upper axils, ovoid, viscous-puberulent, beset 

 with strong, subulate spines somewhat hooked at the apex, two of them 

 thicker and beaked, two-flowered. Hall & Harbour, 264. 



FRANSERIA HOOKERIANA, Xutt. Annual, much branched, l-2 

 high ; leaves ovate in outline, I'-IJ' long, minutely strigose, bipinnatifid, 

 segments oblong or linear; heads~in panicled racemes, fertile ones with 

 several strong, flattened prickles, sterile ones with a 5-8 cleft involucre 

 and 10-20 flowers; chaff of the sterile receptacle small and inconspicu- 

 ous. Hall c(- Harbour, 265. Wet Mountain Valley, Brandegee. Near 

 Denver, Dr. Smith. 



FRANSERIA TENUIFOLIA, Gr., PL FendL, p. 80. Stem erect, hispid; 

 branches diffuse, slender; leaves bipinuatisect, strigose, hirsute, some- 

 what cinereous, pinna* and segments 3-7, linear, entire or 1-2 toothed, 

 sometimes with a few separate lobes on the narrow rachis, terminal 

 lobe very long; raceme spike-form, slender, disposed in a leafy panicle; 

 involucres of the male flowers equaling the pedicel, 7-8 toothed, 6-12 

 flowered, of the female clustered below, armed with a few very short 

 uucinate spines, 2-celled within, 2 -flowered. Xear Pueblo, Greene. 



FRANSERIA DISCOLOR, Nutt. Stems a span high from a creeping 



1 FRAXSEKIA, Cav. Heads of two sorts, the fertile ones at the base, and the 

 sterile ones rum posing the upper portion of the racemes or spikes. Fertile heads with 

 an ovoid or oblong- closed involucre, composed of numerous united scales, the tips free 

 and spiuescent or hooked; corolla none or rudimentary: style with filiform, obtuse 

 branches; achenia oblong: pappus none. Sterile heads hemispherical; the 12-20 

 flowered, cup-shaped involucre of 8-12 united scales: receptacle nattish. with filiform 

 chaff; corolla funnel-shaped. 4-5 toothed, anthers tipped with a slender inflexed ap- 

 endage : ovary none; style radiate-penicillate at summit. Herbs or suftrutesceut 

 plants: the le;ives alternate, coarsely toothed or lobed, or even bipinnatifid. 



