440 SCROPHULARIACEAE (FIGWORT FAMILY) 



Leaves oblong to narrowly lanceolate. 

 Stems strict and slender. % 



Anthers comose 5. P. strictus. 



Anthers short-hirsute . . . . . . 6. P. utahensis. 



Stems ascending-erect, stout. 



Few-flowered; mostly low and dwarf . , . . 7. P. alpinus. 

 Many-flowered; taller . . . . . . . 8. P. glaber. 



Leaves oblong to ovate or subcordate . . . . 9. P. cyananthus. 



Plant pruinose-puberulent. 



Conspicuously so . . 10. P. Fremontii. 



Obscurely so. 



Stems slender, strict . . . . . . 11. P. comarrhenus. 



Stems stout, decumbent . . . . . . . 7. P. alpinus. 



Anther-cells confluent, being dehiscent from the base through their 



junction at the apex. 

 Plant glabrous throughout. 



Distinctly suffrutescent at base. 



Anthers comose 12. P. fruticosus. 



Anthers glabrous 13. P. deustus. 



Herbaceous to the ground (or nearly so). 

 Upper stem leaves oblong to linear. 



Plant tall, 3-12 dm. high 14. P. unilateralis. 



Plant low, mostly less than 3 dm. high. 



Floral leaves enlarged . . . . . . . 15. P. Haydenii. 



Floral leaves reduced. 



Leaves nearly or quite linear. 

 Corolla naked in the throat. 



Lilac or purple (high mountains) . . . 16. P. Hallii. 



Blue (plains and hills) ..... 17. P. angustifolius. 



Corolla bearded in the throat. 

 Stems tufted, simple. 



Flowers purple 18. P. laricifolius. 



Flowers white . . . . . . 19. P. exilifolius. 



Stems branched 20. P. ambiguus. 



Leaves narrowly oblong or oblanceolate . . . 21. P. arenicola. 

 Upper stem leaves ovate or broader. 



The uppermost narrowly ovate, acuminate . . . 22. P. secundiflorus. 

 The uppermost suborbicular. 



Stems 4-10 dm. high; corolla 4-6 cm. long . . . 23. P. grandiflorus. 

 Stems 1-4 dm. high; corolla 2-3 cm. long . . .24. P. acuminatus. 

 Plant more or less pubescent or glandular (at least in the inflores- 

 cence). 

 Stems and leaves glabrous. 



Inflorescence distinctly yerticillate-capitate. 



Sepals green or purplish, at most scarious-margined. 



Flowers small, crowded in the verticils .... 25. P. procerus. 

 Flowers larger, verticils few-flowered . . . . 26. P. Owenii. 

 Sepals lacerate-scarious, with green midrib . . . 27. P. Rydbergii. 

 Inflorescence thyrsoid, either paniculate or glomerate in the 

 axils. 



Thyrsus open 28. P. Watsonii. 



Thyrsus crowded, strict, flowers small. 



Basal leaves mostly oblanceolate ..... 29. P. humilis. 



Basal leaves oval or rotund 30. P. brevifolius 



Thyrsus of crowded axillary glomerules, flowers large . 31. P. glaucus. 

 Stems (at least) and the inflorescence puberulent or more pubescent. 

 Low (2 dm. or less), the persistent base caespitosely and slen- 

 derly many-branched. 

 Leaves linear or nearly so. 



Caudex depressed-caespitose 32. P. caespitosus. 



Caudex woody, more open 33. P. linarioides. 



Leaves narrowly oblong to orbicular. 



Densely pruinose-pubescent 34. P. suffrutescens. 



Glabrate. 



Sepals glabrate 35. P. Crandallii. 



Sepals glandular-villous . . 36. P. Harbourii. 



Taller, rarely tufted (No. 39). 

 Leaves glabrous. 



Corolla blue (about 12 mm. long) 37. P. collinus. 



Corolla lilac-purple or white, longer . . . . 38. P. gracilis. 

 Leaves not glabrous, 



Pruinose-puberulent, obscurely if at all glandular. 



Corolla nearly tubular 39. P. radicosus. 



Corolla abruptly and widely dilated. 



Leaves ovate to narrowly oblong .... 40. P. Jamesii. 



Leavea oblong to linear 41. P. similis. 



Fuberulenl and (above) glandular-hirsute. 

 Sterile filament eomose-bearded. ' 



strongly serrate .... . 42. P. montanus. 

 Leaves nearly entire 43. P. erianthera. 



