EPILOBIACEAE. 247 



lo. MERIOLIX Raf. 



Throat of the hypanthium dark -purple within. i. M. melanoglottis. 



Throat of the hypanthium orange within, sometimes with a darker ring at the 

 base of the stamens. 2. M. serrulata. 



1. Meriolix melanoglottis Rydb. On plains from Tex. to Colo. — " Colo.," 

 exact locality not given. 



2. Meriolix serrulata (Nutt.) Walp. {Oenothera serrulata Nutt.) On 

 plains and hills from Man. and Sask. to Colo, and Ariz. — Alt. 4000-8000 ft. — 

 Boulder; Denver; first range of foot-hills, Larimer Co.; Ft. Collins; Palmer 

 Lake ; Ouray ; Monument ; Manitou Junction ; Pennock's mountain ranch. 



II. Taraxia Nutt. 

 Leaves linear, silky-hirsute. i. T. graciliflora. 



Leaves oblanceolate, glabrous. 2. T. stibacaulis. 



1. Taraxia graciliflora (H. & A.) Raim. Hillsides in California. One 

 specimen collected by Fremont is labeled " Arkansas River, above Pueblo." 

 This may have been a mistake in labeling, as the species is not known east 

 of the Great Basin. 



2. Taraxia subacaulis (Pursh) Rydb. (Jussiaea subacaulis Pursh; Oeno- 

 thera heterantha Nutt.) In valleys from- Mont, and Ida. to Colo, and Calif. 

 — Steamboat Springs. 



12. SPHAEROSTIGMA Nutt. 



Corolla yellow, turning reddish or greenish ; plant hirsutulous below ; often 



glandular above. i. 5". pubens. 



Corolla white or rose-color; plant stigulose or puberulent. 2. S. minutiflorum. 



1. Sphaerostigma pubens (S. Wats.) Rydb. (Oenothera strigulosa pubens 

 S. Wats.) In sandy soil from Ida. and B. C. to Colo, and Calif. — Arkansas 

 River above Pueblo. 



2. Sphaerostigma minutiflora (S. Wats.) Rydb. {Oenothera allysoides 

 minutiflora S. Wats.) In sandy soil from Wyo. to Colo, and Nev. — Grand 

 Junction. 



13. CHYLISMA Nutt. 



I. Chylisma scapoidea (Nutt.) Small. (Oenothera scapoidea Nutt.) In 

 arid soil from Wyo. to Colo, and Utah.— Alt. 4500-7000 ft. — Palisade, bank of 

 Grand River; Cimarron; Grand Junction; Hotchkiss; Canon City. 



14. STENOSIPHON Spach. 



I. Stenosiphon linifolium (Nutt.) Britton. (S. virgatus Spach.) On prai- 

 ries from Neb. and Colo, to Ark., Tex. and Mex. — Exact locality not given. 



15. GAURA L. 



Anthers oval, attached near the middle ; fruit fusiform, sessile, almost equally 

 8-ribbed. i. G. parviflora. 



Anthers linear or nearly so, attached near the base ; fruit strongly 4-angled, 

 at least above. 

 Fruit sessile, broadly fusiform ; tall biennials. 2. G. neo-mexicana. 



Fruit prolonged below into a stipe-like base. 



