382 CARDUACEAE. 



77. PECTIS L. 



i. Pectis angustifolia Torn In " sand-draws " and on sandy hillsides from 

 Neb. and Colo, to Tex. and Ariz. Alt. 4000-11,000 ft Pueblo; Rocky Ford; 

 Little Veta Mountain; Canon City. 



Tribe 6. ANTHEMIDEAE. 

 78. ANTHEMIS L. MAY-WEED, FETID CAMOMILE. 



i. Anthemis Cotula L. In fields and waste places from Newf. and Yukon to 

 Fla. and Calif. Alt. about 5000 ft. Ft. Collins ; Hotchkiss. 



79. ACHILLEA L. YARROW. 



Bracts with light brownish margins. i. A. lanulosa. 



Bracts with dark brown, nearly black margins. 2. A. alpicola. 



1. Achillea lanulosa Nutt. On plains and mountains from western Ont. 

 and Yukon to Ind. Terr, and Calif. ; also Mex. Alt. 4000-12,000 ft. Ft. Col- 

 lins; Arboles; Sangre de Cristo Creek; Cucharas River, below La Veta; 

 Ironton Park, nine miles south of Ouray; along Uncompahgre River, near 

 Ouray; Dark Canon; Ruxton Brook; Seven Lakes; Gunnison; Cerro Sum- 

 mit; mountains between Sunshine and Ward; Raton Range; Dillon Canon, 

 Trinidad; Pike's Peak; Steamboat Springs. 



2. Achillea alpicola Rydb. (A. lanulosa alpicola Rydb.) On high moun- 

 tains from Mont, to Colo. Alt. 11,000-12,000 ft. Little Kate Mine, La Plata 

 Mountains; Seven Lakes; Mt. Ouray. 



80. CHRYSANTHEMUM L. OX-EYE DAISY. 



i. Chrysanthemum Leucanthemum L. Naturalized from Europe from Lab. 

 to Fla., Colo, and Mont. Along Platte River, near Denver. 



81. PICROTHAMNUS Nutt. 



i. Picrothamnus desertorum Nutt. (Artemisia spinescens D. C. Eaton) 

 On arid hills from Mont, and Ida. to N. M. and Calif. Alt. 4000-6000 ft. 

 Palisades, Mesa Co. ; Hotchkiss ; Grand River Canon, above Palisades ; Delta 

 Co. 



82. ARTEMISIA L. WORMWOOD, SAGE-BRUSH. 



Heads heterogamous, i. e., flowers unlike ; disk-flowers hermaphrodite ; marginal 



ones pistillate, truncate, 2-3-toothed. 

 Disk-flowers sterile ; their styles mostly entire, penicillate ; ovary abortive. 



I. DRACUNCULOIDES. 

 Disk-flowers fertile; their styles two-cleft. 



Receptacle with long villous hairs. II. FRIGIDAE. 



Receptacle glabrous. 



Annuals or biennials, tall. III. ANNUAE. 



Perennials. 



Plants not shrubby, except at the base ; leaves not cuneate with 3- 



toothed apex. 

 Plant not at all tomentose ; plant low, 1-3 dm. high. 



IV. ARCTICAE. 



Plant more or less tomentose, at least on the lower surface of the leaves. 

 Involucres densely tomentose. 



