214 FABACEAE. 



Plants with long scattered hairs, not cinereous ; leaflets linear to obovate. 



4. P. hypogaea. 

 Plant cinereous, with short appressed pubescence ; leaflets broadly obovate or 



rounded-spatulate. S- P- mepltiiica. 



1. Psoralea lanceolata Pursh. In sandy soil from Sask. to Colo, and Ariz. 

 — Alt. 4000-7000 ft. — Colorado Springs; Wray; Manitou Junction; La Veta. 



2. Psoralea tenuiflora Pursh. On dry plains and hills from S. D. and 

 Mont, to Ark. and Ariz.^Alt. 4000-8000 ft. — Golden; Cucharas Valley, near 

 La Veta; Canon City; New Windsor, Weld Co.; Eads; Crow Creek; Chey- 

 enne Canon; Colorado Springs; Ft. Collins; plains and foot-hills near 

 Boulder. 



3. Psoralea argophylla Pursh. On plains and prairies from Wis. and 

 Sask. to Mo. and N. M. — Denver. 



4. Psoralea hypogea Nutt. On dry plains from Neb. and Colo, to Tex. 

 and N. M. — Alt. 4000-6000 ft. — Denver; Colorado Springs. 



5. Psoralea mephitica S. Wats. In arid soil from Colo, to N. M. and 

 Calif. — Grand Junction. 



31. PAROSELA Car. 

 Perennials. 



Stem and leaves perfectly glabrous. 



Stem herbaceous ; bracts obovate, persistent, enclosing the calyx. 



1. P. lasianthera. 

 Stem low, suffruticose, branched ; spikes 2-6 flowered ; bracts ovate, deciduous. 



2. P. formosa. 

 Stem and leaves more or less hairy. 



Spike dense, crowded ; petals yellow, at least at first ; plant herbaceous. 

 Leaves digitately tri-foliolate ; plant low and cespitose. 3. P. Jamesii. 

 Leaves pinnately 3-7-folioIate. 



Leaflets of the stem-leaves at least only 3 ; petals turning purplish ; spike 



in fruit about 10 mm. thick. 4. P. elatior. 



Leaflets 5-7 ; petals not turning purple: spike in fruit about 15 mm. thick. 



5. P. aurea. 

 Spike lax ; petals purple. 



Leaves pinnately 3-13 foliolate ; stem scarcely spinose. 6. P. lanata. 

 Leaves uni-foliolate or none ; plant very spiny. 7. P. spinosa. 



Annual ; leaves glabrous. 8. P. Dalea. 



1. Parosela lasianthera (A. Gray) Heller. (Dalea lasianthera A. Gray) 

 In dry soil from Colo, to Tex. and N. M. — Reported from Colorado, but 

 doubtful. 



2. Parosela formosa (Torr.) Vail. (Dalea formosa Torr.) In dry soil 

 from Colo, and Utah to Tex. and Ariz. — Platte River. 



3. Parosela Jamesii (T. & G.) Vail. (Dalea Jamesii T. & G. ; Parosela 

 Porteri A. Nels.) In dry soil from Colo, to Tex. and N. M. — Alt. 4000- 

 6000 ft. — Rocky Ford, Otero Co.; Walsenburg; Cafion City; Florence. 



4. Parosela elatior (A. Gray) Vail. (Dalea nana elatior A. Gray; D. 

 rubescens S. Wats.) Dry places from Colo, to Tex. — " Southeastern Colo- 

 rado." 



5. Parosela aurea (Nutt.) Britton. (Dalea aurea Nutt.) On plains from 

 S. D. to Texas.— "Northeastern Colorado." 



6. Parosela lanata (Spreng.) Britton. (Dalea lanata Spreng.) In dry soil 

 from Kans. and Utah to Tex. and Ariz. ; also in Mex. — On the Platte. 



