BORAGINACEAE. 287 



Corolla 7-8 mm. broad ; nutlets muricate and cross-ridged, but not honey- 

 comb-crested. 5- O. elata. 

 Corolla 4-5 mm. broad; nutlets honey-comb-crested. 



6. O. Bakeri. 

 Sepals lanceolate to linear, much exceeding the nutlets ; inflorescence 



thyrsoid. 

 Inflorescence a broad open round-topped thyrsus ; branches usually 



again branched. 



Tall, 2-4 dm. high ; nutlets with acute backs and sharply acute or 

 slightly winged margins ; tubercles united into more or less dis- 

 tinct cross-ridges. 



Plant light yellowish-green ; nutlets more or less distinctly winged ; 

 cross-ridges of the nutlets rather regular and uniting on the back. 



7. O. hispidissima. 

 Plants dark green; nutlets merely acute-angled and irregularly 



cross-ridged. 8. O. thyrsiftora. 



Low, 1-2 dm. high ; nutlets with rounded backs and merely acutish- 



margined ; muriculations united into almost star-shaped tubercles. 



9. O. aperta. 

 Inflorescence, at least in flower, a narrow, almost spike-like thyrsus ; 



if more open, branches simple. 



Plant green, very hispid ; only the basal leaves canescent ; bristles with 

 very conspicuous pustulate bases, much longer than the short 

 strigose or tomentose pubescence. 



Corolla 7-10 mm. wide ; nutlets ovate, more than half as wide as long ; 

 basal leaves broadly spatulate densely canescent. 



10. O. glomerata. 



Corolla 5-7 mm. wide ; nutlets lanceolate, less than half as wide as 

 long ; basal leaves broadly oblanceolate, somewhat canescent ; 

 plant 1.5-2 dm. high. n. O. perennis. 



Plant canescent ; basal leaves at least with inconspicuous bristles, 

 which are scarcely longer than the other pubescence ; pustulate 

 bases inconspicuous. 

 Plant stout, 3-4 dm. high, rather simple; corolla 7-10 mm. wide. 



12. O. argentea. 

 Plant low, less than i dm. high, densely cespitose. 



13. O. nana. 

 Corolla-tube long-exserted. 



Corolla white. 



Nutlets more or less distinctly rugose with irregular cross-ridges as well 



as muricate. 

 Ridges of the nutlets honey-comb-crested ; inflorescence a narrow thyrsus ; 



leaves canescent and hispid. 14. O. eulophus. 



Ridges of the nutlets neither much interlacing nor crested. 



Inflorescence at least in fruit open with elongated branches ; stem stout. 



15. O. longiflora. 



Inflorescence narrow; stem slender. 16. O. cristate. 



Nutlets finely muricate ; inflorescence at last more or less yellowish ; leaves 



finely canescent. 



Plant cespitose, low, 1-1.5 dm. high; basal leaves 2-3 cm. long, 3-7 mm. 

 wide. 17. O. fulvocanescens. 



Plant 2-3 dm. high; basal leaves 4-8 cm. long, 7-15 mm. wide. 



1 8. O. nitida. 

 Corolla yellow. 19. O. flava. 



1. Oreocarya cinerea Greene. On dry plains of Colo. Alt 5000-7000 ft. 

 Mesas near Pueblo; Canon City; Arkansas River; Rocky Ford. 



2. Oreocarya suffruticosa (Torr.) Greene. (Krynitzkia Jamesii A. Gray) 

 On plains and foot-hills from S. D. and Wyo. to Colo. Alt. 4000-8000 ft 

 Plains and foot-hills near Boulder; Gunnison; Colorado Springs; Denver; 



