GENTIANACEAE. 267 



Upper stem-leaves linear or lance-linear. 



Flower-cluster dense ; its branches and internodes very short. 



5. D. Bigelovii. 

 Flower cluster lax, its branches and internodes elongated. 



6. D. interrupta. 



1. Dasystephana Romanzovii (Ledb.) Rydb. (Gentiana Romansovii 

 Ledeb. ; G. frigida A. Gray ; not Haenke) On alpine peaks and in arctic 

 regions from Mont, and Alaska to Colo, and Utah; also Asia. Alt. 11,000- 

 14,000 ft. Headwaters of Clear Creek; Gray's Peak; Gentian Ridge; Saddle 

 Cliffs ; Mt. Harvard ; Alpine Tunnel ; Mt. Ouray ; Seven Lakes, near Pike's 

 Peak; Georgetown; near Pagosa Peak; Dead Lake, near Pike's Peak; Devil's 

 Causeway, White River Plateau ; Cameron Pass ; Berthoud Pass ; Ethel Peak. 



2. Dasystephana Parryi (Engelm.) Rydb. {Gentiana Parryi Engelm.) In 

 the mountains from Wyo. to Colo, and Utah. Alt. 8000-12,000 ft. Trapper's 

 Lake; Pike's Peak between Half-way House and Lake Mer; near Pagosa 

 Peak ; Westcliffe ; Mt. Harvard ; Artist's Glen near Pike's Peak ; Georgetown ; 

 Seven Lakes; Marshall Pass; Ruxton Park; Grand Lake; Ironton Park, 

 9 miles south of Ouray; Red Mountain road, south of Ouray; Crested 

 Butte; headwaters of Clear Creek; Red Mountain; Breckenridge ; Sprague's, 

 Estes Park ; Leroux Parks, Delta Co. ; Buffalo Pass ; Empire ; mountains 

 between Sunshine and Ward. 



3. Dasystephana affinis (Griseb.) Rydb. (Gentiana affinis Griseb.) In 

 the mountain meadows from Sask. and Alb. to Colo. Alt. 7000-12,000 ft. 

 Mountain meadows, Twin Lakes; Sand Creek Pass; Pike's Peak; Trail 

 Glen; Crystal Park; Lake John, North Park; Colorado Springs; headwaters 

 of Clear Creek, near Empire; between Porter and Durango; Sprague's, Estes 

 Park ; Medicine Bow Mountains. 



4. Dasystephana Forwoodii (A. Gray) Rydb. (Gentiana Forwoodii A. 

 Gray) On hills from Alb. to Colo. Alt. 7000-10,000 ft. Gray's Peak; Sar- 

 gent; Westcliffe; Twin Lakes; headwaters of Clear Creek near Empire; 

 Pearl; Wolcott; Gunnison; Mt. Harvard; Lake City; Buena Vista; Gypsum 

 Creek Canon. 



5. Dasytephana Bigelovii (A. Gray) Rydb. (Gentiana Bigelovii A. Gray) 

 In the mountains from Colo, to N. M. and Ariz. Alt. about 6000 ft. Col- 

 orado Springs ; Pike's Peak ; Sprague's ; Estes Park ; west of Soldier Canon. 



6. Dasystephana interupta (Greene) Rydb. (Gentiana inter up to, Greene) 

 In the mountains from Colo, to Nev. Alt. about 8000 ft. Kremmling; Pa- 

 gosa Springs ; Parlin, Gunnison Co. 



7. PLEUROGYNE Eschsch. 



i. Pleurogyne fontana A. Nels. (P. rotata Hook., in part; not Griseb.; 

 P. rotata tenuifolia Griseb.) In damp places from Hudson Bay and Alaska 

 to Colo. Alt. 8000-11,000 ft. Twin Lakes; near Lake John, North Park; 

 Jefferson, South Park; Caribou; headwaters of Clear Creek, near Empire; 

 Beaver Creek. 



8. SWERTIA L. 



Flowers 4-merous. i. S. scopulina. 



Flowers 5-merous. 



Inflorescence elongated ; corolla-lobes linear or oblong. 2. S. palustris. 



Inflorescence congested ; corolla-lobes oval-elliptic. 3. S. congesta. 



