96 SALICACEAE. 



Ouray; Sheep Creek, above Campton's; Sierra Blanca; near Pagosa Peak; 

 Silver Plume; timber line, Pike's Peak; Ironton Park, nine miles south of 

 Ouray; Mt. Harvard; Red Mountain, south of Ouray; Marshall's Pass; Car- 

 son; Lake Moraine; mountains above Boreas; head of Red River, Frankin; 

 Hematite; Cameron Pass; southeast of Jefferson; Empire. 



26. Salix chlorophylla Anders. In mountain bogs from Lab. to Alaska, N. 

 H. and Colo. Alt 8000-12,000 ft Georgetown ; Clear Creek, Middle Park; 

 Alpine Tunnel; mountains above Boreas; Pike's Peak; Little Kate Basin; 

 Wahatoya Canon ; Buffalo Pass, Park Range ; Red Mountain, south of Ouray ; 

 Columbine; mountains of Estes Park, Larimer Co.; Carson; Marshall Pass; 

 mountains above Boreas; Cameron Pass; Rabbit-Ears, Larimer Co.; Beaver 

 Creek; North Park Range, Routt Co. 



27. Salix petrophila Rydb. (S. arctica petraea Anderson) On exposed 

 mountain tops from N. H. to B. C, Colo, and Utah. Alt. 12,000-14,000 ft. 

 Gray's Peak; near Pagosa Peak; mountains above Boreas; Mt. Howard; 

 Marshall Pass. 



28. Salix saximontana Rydb. (S. reticulata Port. & Coult, in part) On 

 exposed mountain tops from Wyo. to Colo, and Nev. Alt. 9000-14,000 ft. 

 Clear Creek, Middle Park; Arapahoe Peak; Argentine Pass; Floral Moun- 

 tain; Georgetown; Mt Hesperus; mountains above Cameron Pass; Gray's 

 Peak; Bald Mountain; West Spanish Peak; Mount Garfield; Sierra Blanca; 

 Alpine Tunnel; Franklin; Ragged Mountain, Gunnison Co.; Ethel Peak, 

 Larimer Co. 



Order 20. FAGALES. 



Staminate and pistillate flowers both in aments; fruit not with a bur or cup. 

 Staminate flowers 2 or 3 together in the axils of the bracts, each with a calyx ; 

 pistillate flowers without a calyx. 36. BETULACEAE. 



Staminate flowers solitary in the axils of each bract without a calyx ; pistillate 

 flowers with a calyx. 37. CORYLACEAE. 



Staminate flowers in aments ; pistillate often solitary, the involucre becoming a 

 cup or bur. 38. FAGACEAE. 



Family 36. BETULACEAE Agardh. BIRCH FAMILY. 



Stamens 2 ; bracts of the mature pistillate aments membranous, usually 3-lobed, 

 deciduous with the nut. i. BETULA. 



Stamens usually 4 (3-6) ; bracts of the mature pistillate aments thickened and 

 woody, erose or toothed, persistent. 2. ALNUS. 



i. BETULA L. BIRCH. 



Wings of the fruit much wider than the body ; trees or tall shrubs. 



i. B. fontinalis. 

 Wing of the fruit usually narrower than the body ; low shrubs. 2. B. glandulosa. 



i. Betula fontinalis Sarg. (B. occidentalis S. Wats.; not Hook.) Along 

 streams from S. D. and Alb. to Yukon Terr., N. M. and Ore. Alt. 5000- 

 9000 ft. Walsenburg; Garland; Engelmann Canon; foot-hills, Fort Collins; 

 Livermore, Larimer Co.; South Cheyenne Canon; North Cheyenne Canon; 

 Ojo; Pass Creek; foot-hills near Fort Collins; Elizabethtown ; Howe's Gulch; 

 west of Rist Canon ; Rist Canon ; Eldora to Baltimore ; Elk River, Routt Co. 



