EPILOBIACEAE. 247 



10. MERIOLIX Raf. 



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



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 (ix'titt.) Walp. (Oenothera serrulata Nutt.) On 

 plains and hills from Alan, 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. subacaulis. 



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. minntifloruin. 



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 allysoidcs 

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

 Junction. 



13. CHYLISMA Nult. 



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. parviftora. 



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. 



