142 RANUNCULACEAE. 



open woods, in Colo, and N. M.— Alt. 7000-10,000 ft.— Van Boxle's ranch, 

 above Cimarron; Minnehaha; Ojo; hills southeast of La Veta; Veta Pass; 

 Idaho Springs; Mt. Abram, Ouray; chaparral-covered hills southeast of 

 Ouray; Lake City; Cheyenne Canon. 



3. Atragene diversiloba Rydb. In mountains of Colo. — Mountains near 

 Denver. 



4. Atragene tenuiloba (A. Gray) Britton. (Clematis alpina tenuiloba 

 A. Gray.) In mountain woods from S. D. to Mont., Colo, and Ariz.— Alt. 

 7000-10,000 ft.— Placer; Sheep Canon; North Cheyenne Canon; Williams' 

 Canon, above Manitou ; Colorado Springs ; Pike's Peak. 



12. MYOSURUS L. Mouse-tail. 



Achenes with a flat back, only slightly carinate and tipped with a very short 



appressed beak. »■ M. minimus. 



Achenes strongly carinate on the back, tipped with a long subulate ascending beak. 



2. M. aristatns. 



I. Myosurus minimus L. In muddy places and shallow water from Ont. 

 to Wash., Fla. and Calif. ; also in Europe and northern Africa. — Alt. up to 

 5000 ft. — Denver (Eastwood). 



■J.. Myosurus aristatus Benth. In muddy places from Mont, to Wash., Colo, 

 and Calif. — Alt. up to 9000 ft. — ^Long's Peak. 



13. BATRACHIXTM S. F. Gray. White Water-crowfoot. 



Petals 5-7 mm. long, broadly obovate ; stamens many. 



Segments of the leaves 10-15 mm. long, rather rigid, scarcely collapsing when 

 withdrawn from the water. i. B. trichophyllum. 



Segments of the leaves 15-30 mm. long, flaccid, collapsing when withdrawn from 

 the water. 2. B. Aaccidum. 



Petals less than 5 mm. long, oblong-obovate ; stamens 5—12. 



Stem slender; leaves not very flaccid. 3. B. Drouetii. 



Stem filiform; leaves very flaccid. 4. B. confervoides. 



1. Batrachium trichophyllum (Chaix.) Bosh. (Ranunculus aquatilis tricho- 

 phyllus Chaix.) In water from N. S. to B. C, N. C. and Calif. ; also 

 in Mex., Europe and Asia. — Alt. 4000-9000 ft. — Near Ouray; Grizzly Creek; 

 Ft. Collins; Sangre de Cristo Creek; New Windsor; Denver. 



2. Batrachium flaccidum (Pers.) Rupr. (Ranwicuhis aquatilis trichophyl- 

 lus A. Gray, in part) In water from Lab. to Wash., N. C. and Low. Calif. 

 — Alt. 4000-10,000 ft. — Ft. Collins; Trail Creek, near junction with North 

 Poudre; Trapper's Lake; below Carson; Upper Laramie River; Boulder. 



3. Batrachium Drouetii (F. Schultz) Nym. In water from Vt. to Alaska, 

 R. I. and Low. Calif. — Alt. 7000-8000 ft. — Along Uncompahgre River, near 

 Ouray ; Parlin, Gunnison Co. ; Piedra. 



4. Batrachium confervoides Fries. In water from Man. to Alaska, south to 

 Colo. — In Grand Lake. 



14. RANUNCULUS L. Crowfoot, Butter-cup. 



Leaves linear to oval, entire or merely denticulate or crenate ; none divided or cleft. 



Flammulae. 

 Some of the leaves at least cleft. 



Sepals black-hairy. Nivales. 



Sepals not black-hairy. 



