826 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



19. BUCHNERA. Bluehearts 



Perennial, probably root-parasitic; herbage hispid, the hairs pustu- 

 late at base; stem erect, wandlike; leaves mostly opposite, the basal 

 leaves obovate or oblong, larger than the lanceolate or linear stem 

 leaves, usually sparingly dentate; flowers subsessile, in a slender 

 elongate small-bracted spike; corolla dark violet. 



1. Buchnera arizonica (A. Gray) Pennell, Notul. Nat. Acad. Nat. Sci. 

 Phila. 43: 8. 1940. 



Buchnera pilosa Benth. var. arizonica A. Gray, Amer. Acad. 

 Arts and Sci. Proc. 19: 92. 1883. 



Huachuca Mountains (Lemmon 2830, the type collection), August. 

 Southeastern Arizona and Mexico. 



20. CASTILLEJA. 45 Paintbrush 



Plants annual or perennial, herbaceous or barely suffrute scent, 

 often partially root-parasitic; stems leafy, mostly erect; leaves alter- 

 nate, sessile, the blades entire to pinnatifid; flowers very irregular, in 

 conspicuously bracted terminal spikes, the bracts usually colored 

 otherwise than green; calyx tubular, cleft above and below; corolla 

 long and narrow, with a long upper lip (galea), the very short lower 

 lip often reduced to teeth or callosities. 



Most of the species have bright-red floral bracts that are more con- 

 spicuous than the flowers. Where abundant these plants contribute 

 to the forage value of the range for livestock, although it has been dis- 

 covered that C. chromosa takes up large quantities of selenium from 

 certain soils. Plants of this genus are reported to be used medicinally 

 and ceremonially by the Hopi Indians, who ate the flowers of C. 

 linariaefolia. 



Key to the species 



1. Plants usually annual, somewhat viscid; stems tall and often unbranched; 

 leaves and bracts entire, the latter scarlet, at least at the tip; corolla yellow- 

 ish (except sometimes the lip), the lip well developed, much shorter than 

 the galea, thin (not callous), deeply cleft; plants of marshy places (2). 

 2. Steins usually very slender, sparsely villous or glabrate, at least below; 

 leaf blades lance-linear; lip colored differently from the rest of the 

 corolla, bright red 1. C. minor. 



2. Stems usually rather stout, copiously villous nearly to the base; leaf blades 



lanceolate; lip not differently colored 2. C. exilis. 



1. Plants perennial (3). 



3. Bracts and flowers not highly colored, never bright red; galea from slightly 



more to considerably less than 3 times as long as the lip, the latter thin 

 (not callous), deeply cleft, with linear or narrowly lanceolate lobes; 

 bracts (and often some of the stem leaves) pinnatifid, with narrow lobes 

 (4). 

 4. Corolla much longer than the calyx, falcate, 35 to 50 mm. long, ochroleu- 

 cous or purplish, as are sometimes the bracts and the calyx; lip con- 

 spicuous, cleft nearly to the base; pubescence short or somewhat 

 appressed, scarcely lanate (except sometimes on the stems below the 



inflorescence) 3. C. sessiliflora. 



4. Corolla not longer than the calyx, not noticeably falcate, not more than 29 

 mm. long, greenish or yellowish, as are also the bracts and the calyx; 



whole plant conspicuously but loosely lanate 4. C. lineata. 



3. Bracts wholly or partly bright red (except in C. flava) ; galea much more 

 than 3 times as long as the thick, more or less callous, green lip (5). 



Reference: Eastwood, Alice, the Mexican species of castilleja. Amer. Acad. Arts and Sci. 

 Proc. 44: 563-591. 1909. 



