270 



SCROPHULARIACE^. 



Pentstemon. 



Am. Acad. vi. 66; Watson, Bot. King, 219. — Rocky Mountains, Wyoming, W. Colorado, 

 and Utali, NitttuU, Hall & Harbour, Parry, Watson. 



Var. suflfruticosus. A span or more higli from a stouter woody base : leaves from 

 spatulate to obovate and more petioled, thicker, glabrate : sepals less acuminate : corolla 

 and stamens not seen: probably a distinct sj^ecies. — Utah near Beaver, Palmer, in fruit. 



++ -H- Leaves from narrowly linear-lanceolate with tapering base or linear-spatulate to filiform, 

 entire : stems or branches racemosely several-many-flowered. 

 = Stem herbaceous to the base, very simple, afoot or two high; corolla broad : sterile filament 

 glabrous : peduncles mostly opposite. 



P. virgatus, Gray. Minutely glandular-pruinose or glabrous : stem strict and elongated : 

 thyrsus virgate : leaves all linear-lanceolate (H to 4 inches long): jjeduncles short, 1-3- 

 flowered : sej^als ovate : corolla lilac with purple veins, three-fourtlis inch long, abruptly 

 dilated into a broadly campanulate funnelform throat (as wide as long), distinctly bilabi- 

 ate; the broad lips widely spreading: stamens nearly equalling the lips. — Bot. Mex. 

 Bound. 112, & Proc. Am. Acad. vi. 66. — New Mexico and Arizona, /^enc^^er, Wright, &c. 

 Liflorescence and corolla in the manner of P. secundijiorus. 



= == Stems or tufted branches mostly simple from a woody base (or herbaceous in the last 

 species), low : sterile filament longitudinally bearded : short peduncles commonly' alternate. 



P. linarioides, Gray, 1. c. Cinereous, minutely i^ruinose-puberulent : stems much 

 crowded on the woody base, filiform, rigid, very leafy, 6 to 18 inches high : leaves 6 to 12 

 lines long, from oblanceolate-linear (at most a line wide) to nearly filiform, mucronulatc; 

 the floral short and subulate : thyrsus racemiform or sometimes paniculate ; only the lower 

 peduncles 2— 4-flowered : pedicel shorter than the ovate or oblong acuminate sepals : corolla 

 lilac or purple, half inch or more long, with dilated-funnelform throat, less bilabiate than 

 in the preceding ; lower lip conspicuously bearded at base. — Arid grounds, New Mexico 

 and Arizona, Wright, Thurber, Parry, &c. 



Var. Sileri. A dwarf and suffruticulose form, with smaller and fewer flowers, mostly 

 1-flowered peduncles subtended by proportionally longer floral leaves, and the lower lip 

 less bearded. — P. caspilosus, var., Parry in Am. Naturalist, ix. 316, a much reduced form. 

 — S. Utah, Siler, Parry. 



P. Gairdneri, Hook. Cinereous-puberulent : stems a span high, rigid : leaves linear or 

 tlie lower more or less spatulate, obtuse, half to full inch long : thyrsus short and simple : 

 peduncles usually one-flowered : sepals oblong-ovate, glandular-viscid : corolla half inch 

 long, narrowly funnelform, obscurely bilabiate, purple. — Fl. ii. 99; Gray, I.e. — Dry inte- 

 rior of Washington Terr., Oregon, and W. Nevada. 



P. laricif olius, Hook. & Arn. Glabrous : lignescent caudex not rising above the 

 soil: leaves very slender, when dry filiform (the larger a fourth of a line wide, and with 

 margins revolute, an inch or less long), much crowded in subradical tufts and scattered on 

 the (2 or 5 inch long) filiform flowering stems : flowers few, loosely racemose, slender- 

 pedicelled : sejials ovate-lanceolate : corolla tubular-funnelform, half inch long; the small 

 limb obscurely bilabiate. — Bot. Beech. 376 ; Gray, 1. c. — Interior of Oregon and Wyoming. 



= ^ = Stems panicniately branching and slender, woody toward the base : corolla between 

 funnelform and salverform : sterile filament glabrous: peduncles slender, opposite, all the upper 

 one-flowered. 



P. ambigUUS, Torr. Glabrous, a foot or two high, diffuse and often much branched : 

 leaves filiform, or the lowest linear and the floral slender-subulate : inflorescence loosely 

 paniculate: sepals ovate, acuminate: corolla rose-color and flesh-color turning to white ; 

 the rotately expanded limb oblique but obscurely bilabiate ; lobes orbicular-oval ; throat or 

 its lower side somewhat hairy: sterile filament sometimes imperfectly antheriferous. — 

 Ann. Lye. N. Y. ii. 228, & Marcy Rep. t. 16; Gray, Proc. Am. Acad. vi. 64. — Plains of E. 

 Colorado and New Mexico to S. Utah and Arizona. (Adjacent Mex.) Var. /o//os!(s, Benth. 

 1. c, is an undeveloped state. Corolla in the typical form with a narrow and somewhat 

 cm-ved tul)o and throat, of half inch in length : but it passes into 



Var. Thurberi, Gray, 1. c. {P. Thurbpri, Torr. in Pacif. R. Rep. vii. 15), with 

 shorter tube and more dilated throat. The two extremes of this have, in the larger forms, 

 limb of corolla half inch in diameter with tube and throat together only 3 lines long (Ari- 

 zona, Palmer, &c.) ; in the smallest, corolla-limb only half the size, with tube and throat 

 2 or 3 lines long (Arizona and adjacent Mex., Wislizenus, Rothrocl-). New Mexico, Arizona, 

 and S. Utah. 



