266 SCROPHULARIACE.E. PerUstemon. 



P. cristatus, Nutt. Pubescent, or above viscid-villous : leaves from linear-lanceolate to 

 narrowly oblong (1 to 3 inches long) : corolla more funnelform, being less abruptly dilated 

 upward ; its lower lip long-villous within : sterile filament more exserted, inordinately 

 yellow-bearded. — Fras. Cat. & Gen. ii. 52; Benth. 1. c. P. erianthera, Pursh, PI. ii. 737, 

 excl. syn., not Nutt. — Plains, &c, Dakota to Nevada and S. Colorado. 



-j— - ^ — h — h — i — Pruinose-puberulent and glandular ov nearly glabrous : leaves all linear and entire, 

 " narrow at base : corolla large, nearly inch and a half long, funnelform, purple or violet, very 

 obscurely bilabiate; the rounded lobes 2 or 3 lines long: sterile filament wholly glabrous : in- 

 florescence very loose, sometimes simply racemose : sepals ovate or oblong. 



P. dasyphyllus, Gray. A foot high, simple, densely puberulent, and the few-flowered 

 simply racemose inflorescence glandular : pedicels alternate, bracteolate only at base : 

 leaves 3 or 4 inches long, 2 or 3 lines wide (rarely shorter and wider) ; uppermost reduced 

 to subulate bracts : sepals hardly acute. — Bot. Mex. Bound. 112, & Proc. 1. c. — Eastern 

 Arizona and New Mexico. 



P. stenophyllus, Gray, 1. c. Glabrous or obscurely puberulent, 2 or 3 feet high : leaves 

 3 or 4 inches long and the larger only 2 lines wide, attenuate-acute ; the uppermost and 

 floral nearly filiform : thyrsus loosely paniculate : peduncles and pedicels slender : sepals 

 acuminate. — Southern Arizona, Wright. (Adjacent Mex., Wishzenus.) 

 P. lanceolAtus, Benth., of Mexico, may reach our borders. It is minutely puberulent, 



has leaves mostly broader at base, racemose but not quite simple inflorescence, and a "red" 



corolla barely an inch long. 



4— -)— -t— -i-; 4— H— Puberulent, or viscid-pubescent, at least the inflorescence, or sometimes gla- 

 brous : leaves various : corolla from an inch down to 4 lines long, not abruptly catnpanulate- 

 ventricose above, except in P. lavigatus: sepals usually narrow or acuminate. 



++ Leaves from ovate to lanceolate, or the upper cauline when narrower widest at base, undivided : 

 stems erect or ascending : thyrsus mostly many-flowered. 



= Sterile filament bearded along one side, at least toward the apex. 



u. Corolla hardly at all bilabiate, funnelform, with proportionally rather ample and nearly equal 

 spreading lobes, white or whitish, often with a tinge of purple, two-thirds or three-fourths inch 

 long and the limb about as broad: sterile filament thinly short-bearded: leaves entire or barely 

 and sparingly denticulate : thyrsus strict and verticillastriform-interrupted. 



P. tubiflorus, Nutt. Wholly glabrous : stem 2 or 3 feet high, strict, naked above : 

 leaves oblong or ovate-lanceolate ; the floral shorter than the remote and densely-flowered 

 clusters of the much interrupted virgate thyrsus : sepals ovate, merely viscid, only 2 lines 

 long, very short in proportion to the rather slender tube of the corolla. — Trans. Am. 

 Phil. Soc. ser. 2, v. 181 ; Benth. 1. c. — Low prairies, Kansas and Arkansas. Still rare 

 and insufficiently known. Thyrsus a span to a foot long, of several whorl-like clusters. 



P. albidus, Nutt. Viscid-pubescent, 6 to 10 inches high : leaves oblong-lanceolate or 

 narrow : thyrsus strict, leafy below, of approximate few-several-flowered clusters : sepals 

 lanceolate, densely viscid-pubescent, 3 or 4 lines long : corolla with shorter tube and more 

 cyathiform throat. — Gen. ii. 53; Benth. 1. c. P. teretiflorus, Nutt. in Pras. Cat. P. vis- 

 cidulum, Nees in Neuwied Trav. app. 18. —Plains, Dakota to Colorado and Texas. 

 b. Corolla more manifestly bilabiate; lower lip usually somewhat bearded or pubescent within. 



1. Leaves ovate, nil or most of them serrate : corolla bright blue or changing to purple, rather nar- 

 row, half or two-thirds inch long. 



P. pruinosus, Dougl. Stem a foot high, pubescent : leaves from ovate to oblong, glau- 

 cescent, an inch or two long; the radical and lowest and also uppermost cauline commonly 

 entire ; the others acutely and rigidly dentate or denticulate : thyrsus virgate, interrupted : 

 peduncles (several-flowered) and pedicels short; these and the lanceolate attenuate-acumi- 

 nate sepals viscidly villous : lower lip of the deep blue corolla slightly hairy within. — 

 Lindl. Bot. Reg. t. 1280; Benth. 1. c. — Interior of Oregon and Washington Territory, 

 Douglas, Lyall. Little known. 



P. ovatus, Dougl. Stem 2 to 4 feet high, puberulent or pubescent : leaves ovate and 

 the upper subcordate-clasping, all acutely serrate (or the radical rarely entire), bright 

 green : thyrsus looser ; the lower peduncles often longer than the clusters : sepals ovate or 

 oblong, barely acute, glandular : lower lip of the purple-blue corolla bearded in the throat. 

 — Hook. Bot. Mag. t. 2903; Brit. Fl. Gard. ser. 2, t. 211 ; Benth. 1. c — Woods and banks, 

 Oregon to Brit. Columbia and the western part of Idaho. 



