: PENNELL—-SCROPHULARIACEAE OF THE ROCKY MOUNTAINS. 329 
VIII. SPECTABILES. 
A single species. -.....- bocce cee e cence cece cece ee ec eeseeeneesees 19. P. palmeri. 
IX. GLABRI. 
Anther sacs glabrous (or in P. hallii sometimes with a small tuft of hairs precisely 
at the summit of the filament). 
Anther sacs with relatively long line of contact, opening throughout. 
Corolla throat abruptly inflated and decurved at base; sterile filament short- 
bearded (very rarely glabrous); anther sacs with relatively long line of con- 
tact; sepals glandular-puberulent externally, with broad lacerate scarious 
margin. Plants 5 to 25cm. tall.....--------------+++++r++- 20. P. hallii. 
Corolla throat gradually much expanded from the base, not abruptly decurved; 
sterile filament glabrous (very rarely with a few hairs at apex); anther sacs 
with short line of contact; sepals glabrous externally, with or without a 
narrow entire scarious Margin. 
Plants 5 to 10 cm. tall, puberulent; basal leaves 2 to 2.5 cm. long; stem leaves 
few; thyrsus of 1 or 2 1-flowered fascicles; sepals ovate, not or scarcely 
scarious-margined; corolla glabrous within. .....---------- 21. P. parvus. 
Plants 40 to 90 cm. tall, glabrous; basal leaves 6 to 12 cm. long; stem leaves 
numerous; thyrsus of many several-flowered fascicles; sepals oblong-ovate, 
slightly scarious-margined; corolla glabrous or sparsely pubescent within 
anteriorly....  --------+--2-e- erect rrr ster 22. P. unilateralis. 
Anther sacs scarcely contiguous, the line of contact very short. 
Anther sacs opening throughout. 
Sepals narrowly ovate, more or less caudate-tipped, conspicuously scarious- 
mareined, glabrous externally; lower stem leaves narrowly oblanceolate, 
sometimes 12 cm. long......-----.-------- eee e eee eee 23. P. magnus, 
Sepals lanceolate-acuminate, not or obscurely scarious-margined, glandular- 
puberulent externally; lower stem leaves lanceolate, tapering distally, 4 to 
10 em. long.....--------ee reece eee rere etree 24. P. leiophyllus. 
Anther sacs opening partially. 
Plants 40 to 70 cm. tall, glabrous throughout; sepals broadly ovate, more or 
less abruptly acuminate; corolla glabrous externally, the throat more 
inflated anteriorly; sterile filament slightly bearded -....- 25. P. laevis.! 
Plants 20 to 35 cm. tall, cinereous-puberulent throughout; sepals ovate-acumi- 
nate; corolla glandular-puberulent externally, the throat less inflated 
anteriorly; sterile filament glabrous ----.----------+-++---- 26. P. wardii. 
Anther sacs hispid-pubescent to lanate on the sides, scarcely contiguous, the line of 
contact of the sacs very short. 
Anther sacs short-pubescent with relatively atiff hairs. 
Anther sacs opening throughout. 
Corolla 25 to 30 mm. long, the throat much inflated anteriorly and slightly 
narrowed to the orifice, the anterior lobes abruptly deflexed-spreading and 
pubescent or glabrous at base within; sepals not glandular-puberulent ex- 
ternally. 
Sepals 2 to 4 mm. long, nearly orbicular, with short acute or no tip; corolla 
pubescent or glabrous within ....-------+--++++-+++++"- 27. P. glaber. 
Sepals 5 to 7 mm. long, mostly ovate, with more or less prolonged acuminate 
tip. 
1 For description of a related new species, Penstemon tidestromii, omitted in the key, 
see p. 379. 
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