444 SCROPHULARIACEAE (FIGWORT FAMILY) 



obscurely bilabiate; lobes orbicular-oval; throat or its lower side somewhat 

 hairy: sterile filament sometimes imperfectly antheriferous, glabrous. On 

 the plains; eastern Colorado to New Mexico and westward. 



21. Pentstemon arenicola A. Nels. 1. c. 25: 280. 1898. Simple stems 

 2-3 dm. high; entire plant glabrous and stem leaves somewhat glaucous: 

 lower leaves petioled, oblanceolate to broadly spatulate; middle stem leaves 

 4-5 cm. long; upper leaves sessile, oblong to lanceolate, abruptly acute or 

 apiculate: inflorescence short, spiciform, leafy below, the upper bracts short, 

 ovate-lanceolate: sepals broadly lanceolate, slightly scarious, one fourth the 

 length of the corolla-tube: corolla tubular or but slightly inflated upwards, 

 blue, 12-15 mm. long; the lobes oval, spreading, 3 mm. long, naked in the 

 throat: sterile filament equaling the tube, the hooked flattened apex comose, 

 more sparsely hairy down one side for half its length; anthers dehiscent 

 through the junction of the two cells but the cells hardly confluent, not ex- 

 planate. Sandy deserts of central Wyoming. 



22. Pentstemon secundiflorus Benth. 1. c. 325. Glaucous, strict, 1.5-6 dm. 

 high, leafy: leaves firm, entire, the lower and basal ones oblong or spatulate, 

 narrowed into petioles; the upper sessile or clasping, lanceolate or ovate- 

 lanceolate, 5-8 cm. long: thyrsus narrow, sometimes 1-sided: calyx-segments 

 lanceolate, acute, 4-6 cm. long: corolla blue, the tube rather gradually dilated, 

 the limb 2-lipped: sterile filament bearded along the dilated summit: capsule 

 acute, twice as long as the calyx. P. acuminatus. See Rydberg in Bull. 

 Torr. Club 33: 150 on this name and P. secundiflorus. (P. Fendleri Gray, 

 Pac. R. R. Rep. 2: 168.) Sandy plains; Wyoming to New Mexico. 



22a. Pentstemon secundiflorus caudatus (Heller) A. Nels. Leaves all 

 sessile, rather fleshy, oblong-lanceolate below, becoming longer upward and 

 ovate-lanceolate, long-attenuate: flowers pale violet or pinkish. (P. caudatus 

 Heller, Minn. Bot. Studies 2: 34. 1898.) Colorado and New Mexico. 



23. Pentstemon grandiflorus Nutt. in Fras. Cat. 1813. Somewhat glau- 

 cous, stout, 6-12 dm. high: leaves entire, obtuse; the basal obovate, nar- 

 rowed into broad petioles; those of the lower part of the stem sessile, oblong 

 or oval, 2.5-6 cm. long; the upper nearly orbicular, cordate-clasping, shorter: 

 thyrsus open, leafy-bracted, the bracts orbicular-cordate: calyx-segments 

 lanceolate, acute, 6-8 mm. long: corolla lavender-blue, the tube dilated above 

 the calyx, the limb somewhat 2-lipped: sterile filament incurved, villous and 

 capitate at the summit: capsule acute, 1.5-2 cm. high, three times as long as 

 the calyx. On the prairies of the eastern part of our range and thence east- 

 ward and northward to the Mississippi. 



24. Pentstemon acuminatus Dougl. Lindl. Bot. Reg. 15: pi. 1285. 1829. 

 Glabrous throughout or the basal leaves minutely puberulent; stem strict, 

 3-4 dm. high: basal leaves spatulate, petioled, 3-6 cm. long; lower stem 

 leaves also spatulate ; the others ovate or orbicular, often abruptly acumi- 

 nate or mucronate : bracts ovate or orbicular, abruptly short-acuminate : calyx 

 6-8 mm. long; lobes lanceolate, scarious-margined and more or less erose- 

 dentate: corolla pink-purple, 12-18 mm. long, more or less open-funnelform 

 from a narrow tube: anthers glabrous; sterile stamen spatulate at the 

 apex and with a yellow beard. P. acuminatus in part. See note under 

 No. 22 above. (P. cyathophorus Rydb. 1. c. 31: 643. 1904, from which the 

 description here used is drawn.) Sandy plains; Colorado and far northwest- 

 ward. 



25. Pentstemon procerus Dougl. Edinb. New Phil. Journ. 7: 348. 1829. 

 Glabrous throughout; stems slender, 1-4 dm. high: leaves lanceolate, the 

 lower ones petioled, 3-5 cm. long, those of the middle of the stem largest, all 

 usually entire: flowers in 2-5 dense verticillate clusters: sepals oblong or 

 spatulate, with broad, scarious, erose margins, abruptly acuminate or 3- 

 toothed at the apex, about 4 mm. long: corolla bright blue and violet, 10-12 

 mm. long, tubular-funnelform, the lower lip bearded within: sterile filament 

 as long as the others and bearded at the apex. Moist parks and meadows in 

 the mountains; throughout our range and northwestward. 



25a. Pentstemon procerus pseudoprocerus (Rydb.) A. Nels. Sepals not 



