230 Nelson : New Plants from Wyoming 



slightly reduced uppermost leaves : pedicels slender, i 5-20 mm. 

 long : sepals lanceolate, 3-4 mm. long : corolla purple ; its lobes 

 ovate-elliptic, obtuse and usually emarginate, twice as long as the 

 sepals : hoods yellowish with purple center, ovate, obtuse, the base 

 slightly narrowed, as long as the corolla lobes, exceeding the 

 strongly incurved, sickle-shaped horn : anther wings broad and 

 unappendaged : follicles lanceolate-acuminate in outline, 7—10 cm. 

 long, erect on the sharply deflexed fruiting pedicels, mostly densely 

 white tomentose and with a lighter tomentum on the pedicels and 

 peduncles. 



In 1895 I collected this species in flower at Wood's Landing 



(no. 1556) and determined it as A. Hallii Gray. In 1900, I 



secured the same plant in fruit from the same locality (no. 

 I am now convinced that, while it is related to A. Hallii y the 

 relatively long peduncles, the somewhat differently colored flowers, 

 the broader corolla lobes and hoods, the absence of the double 

 gibbosity in the hoods, the sharply deflexed pedicels and the 

 decided tomentum on the erect follicles easily separate it. 



~ Pentstemon exilifolius 



Stems several to numerous, from a tufted, usually much 

 branched caudex from which spring numerous thickened-fibrous 

 roots, glabrous, as are also the leaves and inflorescence, 1 (rarely 

 2) dm. high : leaves very numerous, crowded on the crowns, nar- 

 rowly linear, channelled or involute, subulate-pointed, 15-25 mm. 

 long ; stem-leaves opposite, similar, passing into the smaller 

 bracts : thyrsus narrow (approaching a raceme), crowded, few- to 

 many-flowered ; pedicels slender : sepals ovate-acuminate, the 

 acuminations green, the body scarious-margined : corolla white, 

 tubular-funnelform, 12-15 mm - long, obscurely pubescent in the 

 throat, scarcely bilabiate, the nearly obicular lobes widely spread- 

 ing, 6-7 mm. long : anthers glabrous, the sterile filament scarcely 

 dilated, very stiffly and densely short pubescent. 



This species has been 



Arn., 

 Fort. 



nsidered as P. laricifolins Hook. & 

 Bot. Beechy's Voyage from Snake 

 le interior of Wyoming, closely al- 



lied, were included by Dr. Gray in the description as drawn for 

 the Syn. Fl. The Wyoming specimens that I have seen are 

 clearly distinct. P. laricifolins, the original description shows, has 

 obtusish shining leaves ; the corolla is ventricose ; both the lip 

 and throat are pilose as is also the sterile filament. In P. exili- 

 folius the corolla is almost glabrous and the sterile filament re- 



