SCROPHULARIACEAE (FIGWORT FAMILY) 445 



acuminate, abruptly acute or obtuse: corolla longer, with more dilated, less- 

 bearded throat. (P. pseudoprocerus Rydb. Mem. N. Y. Bot. Gard. 1: 346. 

 1900.) Northern Wyoming and Montana. 



26. Pentstemon Owenii A. Nels. Bot. Gaz. 34: 32. 1902. Allied to the 

 foregoing but the stems lower, obscurely puberulent, 1-2 dm. high: basal 

 leaves crowded, petioled, oblong-elliptic or spatulate; cauline similar but 

 becoming smaller and narrower: thyrsus glandular-pubescent, crowded, capi- 

 tuliform to short-spicate and somewhat interrupted- verticillate : sepals lanceo- 

 late, scarious-margined, with acuminate green tip: corolla violet-blue, tubular, 

 12-15 mm. long: sterile filament stiffly bearded at tip. In the high moun- 

 tains; northwestern Wyoming. 



27. Pentstemon Rydbergii A. Nels. Bull. Torr. Bot. Club 25: 281. 1898. 

 Perennial from horizontal rootstocks which give rise at somewhat regular 

 intervals to vertical branches; from the crowns of these spring long, slender, 

 floriferous stems or very short leafy shoots; glabrous throughout, 3-5 dm. 

 high : radical leaves and those on the sterile shoots oblong, obtuse, on slender 

 petioles as long as the blade or longer; cauline leaves few, sessile by a broad 

 base, narrowly oblong; the lowest pair of bracts leaf-like, broadly linear: 

 the two or more verticils of the interrupted spike many-flowered, the lower 

 one usually distant: sepals scarious, somewhat lacerate-margined : corolla 

 pale blue to purple, 12-16 mm. long, the rounded lobes of the lower lip 

 reflexed, bearded in the throat: sterile filament short-bearded. (P. erosus 



Rydb. Bull. Torr. Bot. Club 28: 28. 1901.) Moist copses; Colorado and 

 Wyoming. 



28. Pentstemon Watsonii Gray, Syn. Fl. 2: 267. 1886. Glaucescent and 

 glabrous throughout, or inflorescence and calyx minutely puberulent, but 

 neither glandular nor viscid; stems 3 dm. or more high, ascending or weak: 

 cauline leaves oblong-lanceolate, acute or acuminate, 3-5 cm. long: contracted 

 thyrsus rather loose; peduncles several-flowered, the lower slender; pedicels 

 longer than the calyx: sepals broadly ovate or orbicular, with a small acumina- 

 tion, somewhat scarious-margined, 2-3 mm. long, barely half the length of 

 the mature capsule: corolla narrowly funnelform, 12-16 mm. long, violet- 

 purple or partly white; lower lip almost glabrous within. Mountains of 

 western Colorado to Nevada. 



29. Pentstemon humilis Nutt. Gray, Proc. Am. Acad. 6: 69. 1866. 

 Stems 1-3 dm. high, glabrous or above with the inflorescence and flowers 

 viscid-pubescent: leaves dark green or rarely glaucescent, oblong to lanceo- 

 late, 2-5 cm. long; the cauline commonly denticulate: thyrsus strict and 

 virgate, 5-10 cm. long; peduncles (2-5-flowered) and pedicels short : sepals 

 ovate or lanceolate and acuminate, lax: corolla rather narrowly funnel- 

 form, 10-14 mm. long, deep blue or partly white; lower lip somewhat hairy 

 within. (P. pseudohumilis Rydb. Mem. N. Y. Bot. Gard. 1: 347. 1900.) 

 In the mountains, rocky canons and stony slopes; throughout our range and 

 westward. 



30. Pentstemon brevifolius (Gray) A. Nels. Caudex subterranean, woody, 

 freely branched, the branches slender, assurgent; stems slender, weak, some- 

 what diffuse, 1-3 dm. long: basal leaves numerous on the crowns and short 

 sterile brunchlets, suborbicular, oval, or oblong, entire, thin, 5-25 mm. long; 

 petioles very slender, as long as the leaves; cauline leaves mostly sessile and 

 oblong spatulate: inflorescence obscurely glandular-pubescent: corolla blue, 

 1 cm. or less long. (P. humilis brevifolius Gray, 1. c.) In the mountains of 

 Utah. 



31. Pentstemon glaucus Graham, Edinb. Phil. Journ. 348. 1829. Glabrous 

 up to the inflorescence, more or less glaucous; stems dwarf or ascending, 

 1-4 dm. high: leaves thickish, oblong-lanceolate or the radical oblong-ovate, 

 3-5 cm. long, entire or denticulate: thyrsus short and compact, either simple 

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

 violet-purple, 20-25 mm. 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 within: sterile filament bearded 



