268 SCROPHULARIACE^. Pentstemon. 



draceous, lilac-purple or sometimes whitisli, three-fourths to nearly an inch long; the 

 throat open. — Gen. ii. 52; Graham in Bot. Mag. t. 2945; Lodd. Bot. Cab. t. 1541; Benth. 

 1. c. P. pubescens, var. gracilis, Gray, Proc. 1. c. partly. — Saskatchewan to Wyoming, and 

 south in the mountains to Colorado. Intermediate between the preceding and following: 

 distinguished from slender forms of the latter by the open mouth and nearly terete throat 

 of the narrow corolla. 

 P. pubescens, Solander. Stem a foot or two high, viscid-pubescent, or sometimes 

 glabrous up to the inflorescence : cauline leaves from oblong to lanceolate (2 to 4 inches 

 long), usually denticulate; the lowest and radical ovate or oblong: thyrsus loosely-flow- 

 ered, mostly naked, narrow: flowers drooping: corolla dull violet or purple, or partly 

 whitish, an inch long, very moderately dilated above the short proper tube, carinate- 

 angled for the whole length of the upper and deeply plicate-bisulcate on the lower side, 

 the upper part of the intrusive portion villous-bearded and forming a sort of palate ; orifice 

 crescentic or almost closed ; the lips and their lobes short : sterile filament densely bearded 

 far down. — Ait. Kew. ii. 360; Sims, Bot. Mag. t. 1424; Gray, I.e. excl. syn. P. IcevigcUus. 

 Chelone hirsuta, L. C. Pentstemon, L. Mant. 415. Asarina caule ererto, &c.. Mill. Ic. t. 152. 

 Pentstemon hirsutus, Willd. Spec. iii. 227. P. Mackayanus, Knowles in Fl. Cab; ii. 117, t. 74. 

 P. lonfjifolitis, Scheele in Linn.xxi. 704? — Dry or rocky grounds, from Canada to Iowa and 

 south to Florida and Texas. 



P. Isevigatus, Solander, 1. c. Mostly glabrous up to the glandular inflorescence : 

 steni 2 to 4 feet high : leaves of firmer texture and somewhat glossy ; cauline ovate- or 

 oblong-lanceolate with subcordate-clasping base, 2 to 5 inches long: thyrsus broader: 

 corolla about an inch long, white and commonly tinged with purple, abruptly campanulate- 

 inflated above the proper tube, more or less obliquely ventricose, obscurely angled down 

 the upper side, not at all intruded on the lower; orifice widely ringent, sparingly slender- 

 bearded at base of the lower lip : sterile filament thinly bearded above. — Sims, Bot. Mag. 

 t. 1425; Michx. Fl. ii. 21; Pursh, Fl. ii. 427. Chelone Pentstemon, L. Spec. ed. 2, 850, excl. 

 syn. Arduin, Moris. &c. ; Lam. 111. t. 528. P. pubescens, var. multiflorus, Benth. in DC. 1. c. 

 (P. Digitalis, var. multijiorus, Chapm.); a small-flowered and small-fruited form, answering 

 to the figure by Lam. P. glancojthi/llus, Scheele in Linn. xxi. 7(33 ? — Moist or rich soil, 

 Penn. to Florida and westward, where the commoner form is 



Var. DigitaliSc Stem sometimes 5 feet high : corolla larger and more abruptly in- 

 flated, white. — P- Digitalis, Nutt. in Trans. Am. P-hil. Soc. n. ser. v. 181 ; Reichenb. Exot. 

 v. t. 292 ; Hook. Bot. Mag. t. 2587 ; Benth. in DC. 1. c. 327 ; Gray, Man. ed. 5, 328. Chelo)ie 

 Digitalis, Sweet, Brit. Fl. Gard. t. 120. Penn. to Illinois, Arkansas, &c. 



P. glaucus, Graham. Glabrous up to the inflorescence, more or less glaucous : stems 

 dwarf or ascending, a span to a foot high : leaves tliickish, oblong-lanceolate or the radical 

 oblong-ovate (one or two inches long), entire or denticulate : thyrsus short and compact, 

 either simple or compound, villous-pubescent and viscid or glandular : corolla dull lilac or 

 violet-purple, less than an inch long, campanulate-ventricose above the very short proper 

 tube, gibbous, not at all plicate-sulcate ; the orifice widely ringent ; the broad lower lip 

 sparsely villous-bearded witiiin : sterile filament bearded mostly at and near the apex only. 



— Edinb. Phil. Jour. 1829, 348; Lindl. Bot. Reg. t. 1286; Gray, Proc. 1. c. P. glaber, var. 

 sfenosepahis, Regel in Act. Petrop. iii. 121 ? — Rocky Mountains north of 49° (Drummond) to 

 Wvoming and Utah ; soutliward, chiefly in the form of 



Var. stenosepalus, Gray, 1. c. Sometimes over a foot high : thyrsus compara- 

 tively small and glomerate : sepals attenuate-lanceolate : corolla dull whitish or purplish. 



— Mountains of Colorado and Utah near the upper borders of the wooded region. 



= = Sterile filament beardless (rarely with a few minute short hairs), sometimes completely 

 antheriferous in certain flowers. 



P. Whippleanus, Gray. Glabrous up to the inflorescence or nearly so : stems slender, 

 a foot long, ascending from a decumbent base, leafy : leaves membranaceous, ovate or 

 ovate-oblong, entire or repand-denticulate, acute or acuminate, commonly 2 inches long; 

 lower petioled ; upper cauline closely sessile or partly clasping by a broad base : thyrsus 

 loosely few-flowered: peduncles 2 to 5, slender, 2-3-flowered : pedicels and the narrowly 

 linear-lanceolate lax and attenuate sepals villous, somewhat viscid : corolla an inch long, 

 campanulate-ventricose above the short proper tube, decidedly bilabiate ; the lower lip 

 longer than the nearly erect 2-lobed upper one, sparsely long-bearded within : sterile fila- 



