OROBANCHACE^E. (BROOM-RAPE FAMILY.) 289 



Order 57. OROBANCHACEiE. (Broom- Rape Family.) 



Root-parasitic herbs, destitute of green foliage, with alternate scales 

 in place of leaves. Flowers hermaphrodite, 5-merous as to perianth, 



with didynamous stamens, solitary in the axils of bracts or scales, some- 

 times on scapiform peduncles, sometimes collected in a terminal spike. 



1. APHYLLON, Mitchell. Cancer-root. 



Flowers pedunculate or pedicellate : calyx 5-cleft : corolla somewhat bila- 

 biate ; upper lip more or less spreading, mostly 2-lobed ; lower spreading : 

 stamens included: style deciduous. — Brownish or whitish, low, commonly 

 viscid-pubescent or glandular plants ; with violet-purplish or yellowish 

 flowers. 



* Peduncles or scapes long and slender from the axils of fleshy loose scales, not 



bracteolate: corolla with elongated somewhat curved tube, and widely spreading 

 somewhat equally 5-lobed limb, only obscurely bilabiate. 



1. A. uniflorum, Gray. Scaly stem short and nearly subterranean, 

 bearing few scapes a span high : calyx-lobes mostly much longer than the tube, 

 subulate, usually attenuate : corolla violet-tinged, the flower an inch long ; the 

 lobes obovate and rather large. — Damp woods ; from Newfoundland to Texas, 

 and westward across the continent. 



2. A. fascieulatum, Gray. More pubescent and glandular : stem often 

 emergent and mostly as long as the numerous fascicled peduncles, not rarely 

 shorter : calyx-lobes broadly or triangular-subulate, not longer than the tube, very 

 much shorter than the dull yellow or purplish corolla ; lobes of the latter oblong 

 and smaller. — From Lake Michigan to Arizona and westward across the 

 continent; on Artemisia, Eriogonum, etc. 



Var. luteum, Gray. A very caulescent and short-peduncled form, with 

 sulphur-yellow corolla, and whole plant light yellow. — Synopt. Fl. ii. 312. 

 Wyoming, Parry. On grasses. 



* * Caulescent, and the inflorescence thyrsoid or spicate: pedicels or calyx 1 to 



2-bracteolate : corolla manifestly bilabiate. 



3. A. multiflorum, Gray. Whole plant viscidly pruinose-puberulent, a 

 span or two high : flowers nearly sessile or the lower ones short-pedicelled : 

 calyx bibracteolate, almost 5-parted into linear-lanceolate lobes, fully half the 

 length of the ample (inch or more long) purplish corolla: anthers very icoolly. 

 — Gravelly plains and pine woods, W. Texas to Arizona, extending into 

 S. Colorado. 



4. A. Ludovicianum, Gray. Rather less pubescent : spikes more fre- 

 quently compound : calyx less deeply and somewhat unequally 5-cIcft : corolla 

 about half smaller ; upper lip sometimes almost entire: anthers (before dehis- 

 cence) glabrous or nearly so. — Phelipcea Ludoviciana, Walp. From the Sas- 

 katchewan to Texas and westward. 



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