

FLOWERING PLANTS AND FERNS OF ARIZONA 291 



7. Inflorescence glabrous or puberulent, the internodes often ringed with a 

 viscid band; bracts very small, much shorter than the fruit (8). 

 8. Fruit not winged; cymules not dense, umbelliform or racemiforrn, the 

 flowers borne on pedicels often more than 2 mm. long. 



8. B. erecta. 

 8. Fruit conspicuously winged: cymules dense, the flowers borne on pedi- 

 cels not more than 2 mm. long (9). 

 9. Wings of the fruit 4 (rarely 3) ; fruit abruptly contracted into a short, 

 winged stipe, the body coarsely transverse-rugose; stems short, 



decumbent or procumbent 9. B. pterocarpa. 



9. Wings 5; fruit not stipitate, the body smooth or nearly so; stems tall, 

 erect or ascending 10. B. megaptera. 



1. Boerhaavia gracillima Heimerl, Bot. Jahrb. 11: 86. 1889. 



Huachuca Mountains, Cochise County {Jones in 1903), also foothills 

 of the Coyote, Baboquivari, and Quijotoa Mountains (western Pima 

 County), 2,600 to 4,300 feet, April to September. Western Texas to 

 Arizona and Mexico. 



The specimens from Pima County have longer, narrower, and 

 thinner leaf blades than those from the Huachuca Mountains. 



2. Boerhaavia caribaea Jacq., Observ. Bot. 4: 5. 1771. 



Yavapai County to Cochise, Santa Cruz, and Pima Counties, 5,500 

 feet or lower, common at roadsides and in fields, May to September. 

 Widely distributed in tropical and subtropical America. 



With its long trailing stems and viscid herbage, this is sometimes 

 an annoying weed in gardens. According to I. L. Wiggins (personal 

 communication) the oldest valid name for this species is B. coccinea 

 Mill. 



3. Boerhaavia wrightii A. Gray, Amer. Jour. Sci. ser. 2, 15: 322. 



1853. 



Coconino and Mohave Counties to Cochise, Pima, and Yuma 

 Counties, 4,000 feet or lower, July to September. Western Texas to 

 Nevada, Arizona, and northwestern Mexico. 



A collection near the base of the Gila Mountains, Yuma County 

 {Harrison and Kearney 6257), approaches B. triquetra S. Wats, of 

 Baja California in its turbinate, truncate, narrowly wing-angled 

 fruits and in having only 2 stamens, but is nearer B. urightii in other 

 characters. This and other specimens from Yuma County may 

 represent an undescribed species. 



4. Boerhaavia spicata Choisy in DC, Prodr. 13 2 : 456. 1849. 



Pinal and Pima Counties, 1,500 to 2,500 feet. Arizona and north- 

 ern Mexico. 



5. Boerhaavia torreyana (S. Wats.) Standi., Contrib. U. S. Xatl. 



Herbarium 12: 385. 1909. 



Boerhaavia spicata var. torreyana S. Wats., Amer. Acad. Arts 

 and Sci. Proc. 24: 70. 1889. 



Navajo, Coconino, Yavapai, and Maricopa Counties, 1,100 to 

 5,000 feet. Western Texas and Coahuila to southern California. 



