766 SCROPHULARIACEAE 



Corolla glabrous within, less than 2 cm. long; calyx-lobes lanceolate, 4-5 mm. 



4o. i . 



Corolla-tube funnelform, scarcely gibbous; sterile stamen sparingly yellow-yillous above; 

 corolla white. 44 - p - albtdus. 



XI. HARBOURIANI. 

 One species. 45 - p - Harbourii. 



XII. CONFERTI. 



Sterile fllament usually naked; leaves sharply dentate. 46. P. deustus. 



Sterile filament bearded; leaves entire or denticulate. 

 Calvx glabrous or puberulent but not glandular. 



Corolla sulphur-yellow. 47. P. confertus. 



t long; lobes rounded-ovate, acute, denticulate; leaves thin, the 

 upper acuminate. 48. P. Watsonii. 



Calyx 5-6 mm. long; lobes ovate, abruptly acuminate or obtuse; leaves firm, 



not acuminate. 

 Corolla more than 1 cm. long; upper stem-leaves broadly lanceolate, often 



rounded at the base; plants 3 dm. high or more. 

 Calyx-lobes ovate, acuminate. 49. P. Rydbergii. 



Calyx-lobes broadly obovate, obtuse or abruptly short-acuminate. 



50. P. laxus. 

 Corolla less than 1 cm. long; limb small; upper stem-leaves linear-lanceo- 



late ; plant seldom more than 3 dm. high. 51. P. procerus. 



Calyx and inflorescence more or less glandular. -* 



Leaves more or less denticulate. 



Upper stem-leaves broad, ovate-cordate, acuminate, clasping. 



Stem pubescent; calyx-lobes not scarious. 52. P. ovatus. 



Stem glabrous or sparingly puberulent up to the inflorescence; calyx-lobes 



margined. 

 Leaves firm; inflorescence rather dense; calyx-lobes narrowly scarious- 



margined. 53. P. pinetorum. 



Leaves thin; inflorescence open; calyx-lobes not scarious- margined. 



54. C. leptophyllus. 

 Upper stem-leaves lanceolate or linear. 



Calyx-lobes elongate-lanceolate, not scarious; flowers ascending; stem- 



leaves linear-lanceolate or linear. .62. P. gracilis. 



Calyx-lobes ovate-lanceolate, scarious-margined below and usually toothed ; 



stem-leaves oblong-lanceolate or lanceolate. 



Tall, 3-5 dm. high; calyx-lobes acute. 55. P. Wilcoxii. 



Low, less than 3 dm. high; calyx-lobes abruptly acuminate. 



60. P. virens. 

 Leaves entire or essentially so. 



Plant depressed, decumbent; stems less than 2 dm. high; basal leaves usually 

 less than 3 cm. long, with rhombic-ovate or rounded-spatulate blades. 

 Corolla about 1.5 cm. long; stem-leaves more or less denticulate. 



56. P. albertinus. 



Corolla 1 cm. long or less; stem-leaves entire. 57. P. brevifolius. 



Plant not depressed, 2-7 dm. high; basal leaves more than 3 cm. long, with 



oblanceolate blades; corolla 1.5 cm. long or more. 

 Calyx-lobes ovate, broadly scarious-margined. 



Corolla sulphur-yellow. 58. P. atlenuatus. 



Corolla purplish. 



Stem-leaves ample, lanceolate or oblong. 

 Stem and leaves glabrous or nearly so. 



Leaves thick, darkening in drying; stem-leaves always entire; 

 inflorescence interrupted, congested. 



59. P. pseudoprocerus. 



Leaves thin, not darkening in drying; stem-leaves usually den- 

 ticulate; inflorescence not congested, a more or less contin- 

 uous panicle. 60. P. virens. 



Stem and leaves decidedly puberulent. 68. P. humilis. 

 Stem-leaves linear or linear-lanceolate, reduced; basal leaves numer- 



ous, oblanceolate to almost linear. 61. P. aridus. 



Calyx-lobes narrowly lanceolate, slightly scarious-margined. 



Leaves thick and darkening in drying; inflorescence congested and 



interrupted; corolla dark blue-purple. 



Plant 2-3 dm. high; upper stem-leaves linear-lanceolate or oblong. 



62. P. pseudohumilis. 

 Plant 5-7 dm. high; upper stem-leaves ovate-lanceolate, less than 



half as long as the internodes. 50. P. laxus. 



Leaves thin, light green, not darkening in drying; inflorescence a con- 

 tinuous panicle; corolla white, light blue, or pink; leaves linear 

 or linear-lanceolate. 

 Stem glabrous or nearly so. 



Inflorescence narrow; pedicels short; stem-leaves linear-lanceo- 



late. 63. P. gracilis. 



Inflorescence open; pedicels long; stem-leaves narrowly linear. 



64. P. oliganthus. 

 Stem densely puberulent. 



