FLOWERING PLANTS AND FERNS OF ARIZONA 837 



the sore. The Navajo Indians are reported to use a decoction of the 

 plant for this purpose. The entire plant, or the underground parts 

 only, were eaten by the southwestern Indians. Some of the Old 

 World species are parasitic on clover and other cultivated plants. 



Key to the species 



1. Flowers not subtended by bractlets, few, in loose fasciculate inflorescences; 

 pedicels commonly much longer than the flowers; corolla somewhat falcate: 



See" lis 1. O. FASCICTJLATA. 



1. Flowers subtended by bractlets, many, in dense, spikelike inflorescences, these 

 netimes branched below: pedicels none or shorter than the flowers; 

 corolla straight or nearlv so, brownish purple and white: Section Myzorrhiza 

 (2). 



2. Corolla lobes rounded 2. 0. multiflora. 



2. Corolla lobes narrowed toward the acute or acutish apex. 



3. O. LUDOVICIAXA. 



1. Orobanche fasciculata Nutt., Gen. PL 2: 519. 1818. 



Navajo, Coconino, and Mohave Counties to Cochise and Pima 

 Counties, 4.000 to 8.000 feet, mostly in chaparral and in coniferous 

 forests, May to August. Michigan to British Columbia, south to 

 Texas. Arizona, and southern California. 



Both the typical form, with the plant and the corolla brownish 

 purple, and var. lutea (Parry) Achey (Phelipaea lutea Party), with the 

 plant and the corolla dull yellow, sometimes tinged with pink, occur 

 in Arizona, the latter being the commoner form. Arizona specimens 

 with exceptionally large corollas, therein approaching var. franciscana 

 Achey, are not infrequent. The plants are parasitic on Artemisia 

 trideniaia, Eriogonum wrigktii, and other plants. 



2. Orobanche multiflora Nutt., Acad. Nat. Sci. Phila. Jour. ser. 2, 1: 



179. 1848. 



Apache. Navajo, and Pima Counties (doubtless elsewhere), 5,000 

 to 6.000 feet, sandy soil, April to July. Wyoming to Washington, 

 south to northern Mexico and southern California. 



Most of the Arizona specimens belong to var. arenosa (Suksdorf) 

 Munz, with corolla lips not more than 5 mm. long. A collection in the 

 Santa Catalina Mountains (Pringle in 1884) with lips 6 to 7 mm. long 

 represents var. pringlei Munz. heretofore reported only from Chihua- 

 hua. 



3. Orobanche ludoviciana Nutt., Gen. PI. 2: 58. 1818. 



Navajo and Coconino Counties to Pima. Santa Cruz, and Yuma 

 Counties, 500 to 7,000 feet, March to July. Southern Utah and 

 Nevada to western Texas, Arizona, southeastern California, and 

 northwestern Mexico. 



Two intergrading forms occur in Arizona. These are: (1) var. 

 cooperi ( A. Gray) G. Beck (O. e<><>p(ri A. Gray), with lips of the corolla 

 3 to 6 mm. long and lobes of the lower lip lanceolate, tapering gradually 

 to an acute tip; (2) var. latUoba Munz, with lips of the corolla 6 to 9 

 mm. long and lobes of the lower lip oblong or oblong-ovate, narrowed 

 abruptly at apex. The latter form occurs only in the southern part of 

 the State. The plants are normally parasitic on Franseria ami other 

 Compositae, but specimens of var. cooperi collected near Flagstaff 

 showed attachment to roots of cacti (Opuntia, Echinocact 



