428 MISC. PUBLICATION 42 3, IT. S. DEPT. OF AGRICULTURE 



4. Hoffmanseggia densiflora Benth. in A. Gray, PL Wright. 1: 55. 

 1852. 



Larrea densiflora Britton, North Amer. Fl. 23: 311. 1930. 



Navajo County to Mohave County, south to Cochise, Pima, and 

 Yuma Counties, 5,000 feet or lower, April to September. Kansas to 

 Arizona, southern California, and central Mexico. 



Hogpotato, camote-de-raton. Common at roadsides in the irrigated 

 districts, often forming large colonies and becoming a troublesome 

 weed in cultivated fields and pastures, difficult to eradicate, espe- 

 cially on heavy soils. The tuberous enlargements of the roots are 

 valuable hog feed and after roasting were used for food by the 

 Indians. The plant is considered a good soil binder. 



The species is closely related to the South American H.falcaria Cav., 

 to which it was reduced by Fisher. 64 He described several varieties 

 under H. falcaria of which the following were stated to occur in 

 Arizona: var. stricta (Benth.) Fisher; var. demissa Fisher; var. pringlei 

 Fisher (type, near Tucson, Pringle in 1881, part); and var. capitata 

 Fisher (type, near Tucson, Pringle in 1881, part). 



13. CAESALPINIA 



Shrub, up to 3 m. (10 feet) high; leaves bipinnate, large, with many 

 small leaflets; flowers in terminal racemes, large and showy, the petals 

 yellow; stamens and pistil red, the stamens w T ith very long filaments; 

 pods large, flat. 



1. Caesalpinia gilliesii Wall., Bot. Misc. Hook. 1: 129. 1830. 



Poinciana gilliesii Hook., ibid. 



Occasionally escaped and perhaps naturalized near Kingman (Mo- 

 have County), Globe (Gila County), and in Cochise and Pima Counties, 

 May to August. Introduced from South America. 



Bird-of-paradise-flower. Much grown as an ornamental, especially 

 by the Mexican population. Plant ill smelling, very showy because 

 of the extraordinarily long red filaments. 



3. Papilionoideae. bean subfamily 



Key to the genera 



1. Filaments all separate to the base or very nearly so (2). 



2. Leaves pinnate with numerous leaflets; stipules very small; corolla white, 

 blue, or lilac; pods torulose; plants small herbs or good-sized shrubs. 



14. Sophora. 



2. Leaves digitately 3-foliolate; stipules large, foliaceous; corolla yellow; pods 



not torulose; plant a tall herb 15. Thermopsis. 



1. Filaments all, or 9 of them, united at least near the base or, if separate 

 (Parry ella) , then attached at base to the calyx, and corolla none (3). 



3. Anthers strongly differentiated, some very small and versatile (dorsifixed) , 



others much larger and basifixed; plants herbaceous (4). 



4. Leaves unif oliolate or pinnately trif oliolate ; corolla yellow or orange ; pods 

 much inflated, bladderlike ; plants annual 16. Crotalaria. 



4. Leaves palmately compound with usually more than 3 leaflets; corolla 

 violet, purple, or whitish; pods not bladderlike; plants annual or 

 perennial 17. Lupinus. 



» 4 Fisher, E. M. revision of the north American species of hoffmanseggia. Contrib. IT. S. Natl. 

 Herbarium 1: 143-150. 1892. (See pp. 144, 145.) 



