BRASSIACEAE. 155 



Basal leaf-blades oblanceolate. , 



Plant usually over 3 dm. high ; flowers and fruit corymbose. 



9. L. Bngelnianni. 

 Plant usually less than 3 dm. high ; inflorescence at least in fruit elongated, 

 racemose. 10. L. stenophylla. 



Basal leaves broadly oval. 11. L. ovalifolia. 



L. Lesquerella Shearis Rydb. On plains and foot-hills of Colo. — Alt. 5000- 

 8000 ft. — Boulder ; Palmer Lake ; Idaho Springs. 



:i. Lesquerella curvipes A. Nels. On dry hills from Mont, to Colo. — Alt. 

 up to 10,000 ft. — ^Como. 



3. Lesquerella alpina (Nutt.) S. Wats. {Vesicaria alpina Nutt.) Dry Hills 

 from N. D. and Mont, to Colo. — Florence; North Park. 



4. Lesquerella parvula Greene. On dry hills in Colo. — Mt. Bross, Middle 

 Park. 



5. Lesquerella prostrata A. Nels. In dry places, in the mountains, from 

 Ass. to Colo. — Alt. 5000-8000 ft. — Northern State line; mountain near Veta 

 Pass; between La Veta and Gardner. 



6. Lesquerella montana (A. Gray) S. Wats. {Vesicaria montana A. Gray) 

 On hillsides and in the mountains from Wyo. to N. M. — Alt. 5000-11,000 ft. 

 — Larimer Co. ; Horsetooth Gulch ; Palmer Lake ; Fossil Creek ; Ft. Collins ; 

 Rist Cafion, Larimer Co.; Salida; Mancos; Trinidad; mesas near Colorado 

 Springs ; river bluffs north of La Veta ; Los Pinos ; plains near Denver ; hills 

 southeast of La Veta ; Manitou ; Veta Pass ; South Park. 



7. Lesquerella arenosa (Richardson) Rydb. On dry hills from Sask. to 

 S. D. and Colo. — Dolores. 



8. Lesquerella argentea (Pursh) MacM. (Vesicaria Ludoviciana DC.) 

 On plains and dry hills from Minn, to N. D., Kans. and Colo. — -Wray; north 

 of Craig, Routt Co. ; Clear Creek ; 25 miles below Manitou. 



g. Lesquerella Engelmanni (A. Gray) S. Wats. On dry mesas from Kans. 

 and Colo, to Tex. and N. M. — Pueblo. 



10. Lesquerella stenophylla (A. Gray) Rydb. {Vesicaria stenophylla A. 

 Gray and V. Fendleri, in part.) On dry mesas from Colo, to Tex. and N. M. ; 

 also in Mex. — Alt. 4000-5000 ft. — Florence ; Swallow's, between Pueblo and 

 Caiion City; mesas near Pueblo; Brantly Carion, Las Animas Co.; Pueblo. 



11. Lesquerella ovalifolia Rydb. (L. ovata Greene.) On dry mesas and 

 hillsides from Neb. to Colo, and Kans. — ^Alt. about 1500 m. — Mesas near 

 Pueblo. 



10. RORIPA Scop. Water-cress. 



Aquatics, usually immersed and rooting, with pinnate leaves and white petals. 



1. R. Nasturtium. 

 Terrestrial or marsh plants with pinnatifid leaves and yellow petals (except in 

 R. trachycarpa. 

 Perennials with rootstocks ; petals much exceeding the sepals. 

 Pods pappillose. 



Leaves thin ; petals white ; fruit recurved. 2. R. trachycarpa. 



Leaves thick ; petals yellow ; fruit erect. 3. R. calycina. 



Pods not papillose. 4. R. sinuata. 



Annuals or biennials. 



Pods spherical to oblong-ellipsoid ; in the latter case shorter than the pedicels. 

 Pedicels 4-10 mm. long; pods 3-5 mm. long (rarely 6-7 mm. in R. palustris) , 

 1.5-2 mm. thick. 



