SCROPHULARIACBAE (FIGWORT FAMILY) 443 



proper tube of nearly twice the length of the calyx, abruptly dilated into the 

 broadly campanulate throat of about 8 mm. in height and width; this nearly 

 equaled by the widely spreading lips; the lobes round^oval: sterile filament 

 glabrous or minutely bearded atthe dilated tip. P. secundifloms. — In the 

 mountains of Colorado and Wyoming. 



15. Pentstemon Haydenii Wats. Bot. Gaz. 16: 311. 1891. More or less 

 glaucous; stfem decumbent, leafy, 3*-6 dm. high: leaves linear or elongated* 

 lanceolate, entire, sessile and slightly olaspmg^ acute, acuminate, or the lowest 

 obtusish, 5-13 cm. long, 2-10 mm. wide: thyrsus narrow, dense; bracts ovate 

 or ovate-lanceolate, large, cordate-clasping, acute or acuminate: calyx- 

 segments lanceBlate, striate-nerVed, acuminate, 6-10 mm. long: corolla blue, 

 the tube broadly dilated above the caAyn, the limb nearly equally 5-lobed: 

 capsule acute, twice as long as the calyx. — In Kansas and Nebraska and the 

 eastern part of our range-. ,; 



16. Pentstemon Hallii Gray, Proc. Am. Acad. 6: 71. 1866. Stems 1-2 dm. 

 high: leaves thickish, linear and linear-spatulate, or the lowest rather broader, 

 obtuse: thyrsus short and spiciformj 5-15-flowered, obscurely viscid: sepals 

 broadly ovate and with widely Bcarious; erose margins: corolla 15-20 mm. long, 

 broadly campanulate-inflated from a thickish and inconspicuous proper tube 

 which is shorter than' the calyx; bilabiate limb rather short: sterile filament 

 short-bearded from the apex downward.^ — ^In the Colorado mountains at high 

 elevations. , , 



• 17. Pentstemon angusMfolius Pursh; PI. Am. Sept. 738. 1814. Glaucous; 

 stem slender, leafyj'ii5-^2 dmihigh: leaves linear or liuear-lanceolate, entire, 

 tnfe Idwer narrowed into petioles, obtusish, the upper sessile acute, 3-6.5 cm. 

 loUg,' 3-4f mm. wide; thyrsus narrow, spike-hke, mostly dense; bracts lanceo- 

 late, 'acuminate; pedicels very short: calyx-segments linear-Lanceolate, acu- 

 minate,- 4-6 mm. long: corolla blue or nearly white, the tube gradually: en- 

 larged] the hmb somewhat 2-lipped: sterile filament bearded at the summit. 

 P. caeruleus. — In dry soil; from the base of the mountains to Nebraska aiid 

 Dakota. ' . ' ■ 



18. Pentstemon laricifolius H. <fc A. Bot. Beech, 376. 1841. Glabrous; 

 stems tufted, 5-18 cm. high; lignescent caudex not rising above the soil: 

 leaves slender, when dry filiform and with the margins revoJute, the larger 

 •1-2 mm. wide, 2—4 cm. long, much crowded in subradical tufts and scattered 

 OB the slender flowering stems: flowers few, loosely racemose, slender-pediceled: 

 sepals' ovate-lanceolate:- corolla tubular-funnelform, 12-18 mm. long, purple, 

 the smaU limb obscurely bilabiate: sterile filament bearded on the upper side. 

 {P. hxUifoKus desertus A. Nels.' 1. c. 28: 231; P. aridps Rydb. Mem. N. Y. 

 Bot.'Gard. 1: 348. 1900, much resembles this but has a glandular-pubescent 

 iaflorescence with "blue " flowers. It occurs in the arid plains of Montana.):^- 

 P. laricifolius was described from Oregon plants, but aside from the greater 

 size in every way ours from Wyoming and Colorado do not seem to differ 

 essentially. 



19. Pentstemon exilifolius A. Nels. 1. c. 28: 230. Stems |, several to nu- 

 merous, frdmi a tufted branched caudex, glabrous, as are alsothp leaves and 

 inflorescence, 1 (rarely 2) dm. high: leaves very numerous, crowded on the 

 crowns, narrowly Unear, channeled or involute, subulate-pointed, 15-25 mm. 

 long; stem leaves similar, passing into the smaller bracts: thyrsus narrow, 

 crowded, few to many-flowered; pedicels slender: sepals lanceolate and long- 

 acuminate, erose, scarious-margined: corolla white, tubular-funnelform, 

 12-15 mm. Icing,- obscurely pubescent in the throat, scarcely bilabiate, the 

 nearly orbicular lobes widely spreading, (6-7 .mm. long: anthers glabrous, the 

 Sterile' filament scarcely dilated, very stifily and densely short-pubescent. — 

 Dry 'stoiiy plains and hills; Wyoming and northern Colorado. ■ . 



' 20. Pentstemon ambiguus Torr. 1. c. 2: 228. 1828. Glabrous, 2-5 dm. 

 Mgh, diffuse and often' much brancheds leaves filiform, or the lowest linear 

 'and the floral slender-subulate :'inflorfecence loosely paniculate: sepals ovate, 

 acuminate: corolla Tose-color and flesh-color turning to white,, narrow and 

 somewhat curved, about 12 mm. long, the scarcely expanded, limb oblique but 



