(397 ) 
7. PAROSELA sPINosA (A. Gray) Heller, Cat. N. Am. 
Pied. 12,9... 1900. 
Dalea spinosa A. Gray, Mem. Am. Acad. II. 5: 315. 1855. 
Asagraea spinosa Baillon, Adansonia 9: 233. 1870. 
Type locality: “Arroyos on the Gila; and on the California 
desert west of the Colorado.” 
Distribution: Western borders of the Colorado Desert, and 
extending eastward to southern Arizona, and southward into 
Lower California. Lower Sonoran. 
Specimens examined: Palm Springs, Hall 5758; Carriso Creek, 
Abrams 3980. 
6. OLNEYA. Ironwoop. 
1. Otneya Tesota A. Gray, Mem. Am. Acad. II. 5: 328. 1855. 
Type locality: “On the table-lands of the Gila,” and “near 
Bill Williams’ Fork,” Arizona. 
Distribution: The Colorado Desert of southern California, 
eastward into Arizona, and southward into Lower California and 
Sonora. Lower Sonoran. 
Specimens examined: Signal Mountain, Abrams, Dec. 29, 1907. 
ZYGOPHYLLACEAE. Cattrop Famity. 
1. COVILLEA. CREosoTE-BUSH. 
1. COVILLEA TRIDENTATA (Moc. & Sesse) Vail, Bull. Torr. 
Bot. Club 26: 302. 1899. 
Zygophyllum tridentatum Moc. & Sesse; DC. Prod. 1: 706. 
1824. 
Zygophyllum californicum Torr. & Frem. in Frem. Second Rep. 
257; / O45. 
Type locality: “In regno Mexicano.” 
Distribution: The most common and widely distributed shrub 
of the desert districts of southern California, extending eastward 
to western Texas, and southward through the arid regions of 
Mexico and Lower California. Lower Sonoran. 
Specimens examined: Willow Springs, Abrams 3 McGregor 424; 
Lancaster, Elmer 3664; Cushenberry Springs, Abrams 2147; Im- 
perial Junction (Old Beach), Abrams 3202; Jacumba Hot Spring, 
Abrams 3675. 
