244 EPILOBIACEAE. 



3. Gayoyhytum Nuttallii T. & G. On hillsides from S. D. and Wash, to 

 Colo., Ariz.- an d Calif. Alt. 6000-8000 ft. Parlin, Gunnison Co.; foot-hills, 



Larimer Co. 



4. Gay ophy turn race*? 1 osum T- & G. In sandy soil from Wyo. and Wash, to 

 Colo, and Calif. Alt. soooXJ 2 . 000 ft. Headwaters of Clear Creek; Veta 

 Pass; above Mancos; along the t?P_udre. 



*-, 



4. ONAGRA Adans. EVENING PRIMROSE. 



Hypanthium slender, 2.5-5 cm - long. 



Petals 1-2 cm. long, yellow ; pubescence rarely hirsute. 



Plant green; capsule 3-4 cm. long. ' O. Oakesiana. 



Plant grayish strigose ; capsule 2-3 cm. long. 2 - O. strigosa. 



Petals 2-3.5 cm. long, often pinkish ; plant more or less*. nirsute - 



. 3- O. Hookeri. 



Hypanthium stout, 6-13 cm. long. 4.- O. Jamesii. 



1. Onagra Oakesiana (A. Gray) Britton. (Oenothera OakesianP A. Gray) 

 In rich valleys from Que. and S. D. to N. Y. and Colo. Alt. up to ic 1 - 000 ft. 

 Salida ; North Cheyenne Canon ; Valley Spur. 



2. Onagra strigosa Rydb. In valleys and on plains from Minn, and Wash. 

 to Kans., N. M. and Utah. Alt. 4000-7000 ft. Ft. Collins ; Colorado Springs ; 

 Gunnison ; Elk River, Routt Co. ; Engelmann Canon ; Poudre Canon ; G~yP~ 

 sum ; soldier Canon. 



3. Onagra Hookeri (T. & G.) Small. (Oenothera Hookeri T. & G. ; 0- 

 biennis hirsutissima A. Gray) In valleys from Ida. to N. M. and Calif.; 

 also Mex.- Alt. 6000-10,000 ft. Black Canon of Gunnison; Canon City, 

 Fremont Co. ; Pagosa Springs ; Parrott Post Office ; west of Ouray ; Waha- 

 toya Creek; Pike's Peak; Durango; along Conejos River north of Antonito. 



4. Onagra Jamesii (T. & G.) Small. (Oenothera Jamesii T. & G.) In 

 dry soil from Okl. and Utah to Tex. and Ariz. On Platte River (?). 



5. ANOGRA Spach. WHITE EVENING PRIMROSE. 



Calyx in bud merely acutish ; tips not free. 



Capsule divergent or reflexed. i. A. violacea. 



Capsule erect or ascending. 2. A. albicaulis. 



Calyx in bud acuminate or acute ; tips free. 



Capsule linear-cylindric ; throat of the calyx glabrous. 



Calyx sparingly long-hairy, glandular-puberulent or glabrous, not strigose. 

 Leaves deeply pinnatifid. 3. A. rhizomata. 



Leaves subentire, dentate or short-lobed. 



Capsules strongly ascending, straight ; leaves linear, entire or nearly so, 



strigose beneath. 4. A. Nuttallii. 



Capsules divergent, usually curved upwards ; leaves usually denticulate 



or sometimes lobed. 



Leaves glabrous, except the margins. 5. A. Vreelandii. 



Leaves pubescent on both sides. 6. A. cinerea. 



Calyx and hypanthium densely grayish strigose ; leaves cinerous. 



7. A. latifolia. 

 Capsules oblong ; throat of the calyx hairy ; leaves deeply pinnatifid. 



8. A. coronofifolia. 



i. Anogra violacea A. Nels. In sandy soil of Wyo. and Colo. Alt. 4000- 

 5500 ft. Deer River; Palisades; Hotchkiss. 



