( 387 ) 
1898; Abrams 2054; Imperial Valley, near Calexico, Abrams 
3999- 
CAESALPINIACEAE. Senna Famity. 
Leaves simple, rounded; flowers resembling the papilionaceous, purple. 
1. Cerets 
Leaves 1-2-pinnate; flowers regular, yellow. 
Pods not compressed, torose, gland on upper petal wanting. 
2 
. Parkinsonia. 
Pod compressed, only slightly contracted between the seeds; gland on 
upper petal prominent. 3. Cercidium. 
1. CERCIS. Rep-sup. 
1. CERCIS OCCIDENTALIS Torr.; A. Gray, Bost. Journ. Nat. Hist. 
> 177. 1850 
Cercis californica Torr.; Benth. Pl. Hartw. 361. 1857. 
Siliquastrum occidentale Greene, Man. Bay Region, 84. 1894. 
Type locality: “Rocky plains of the Upper Guadaloupe.” 
Distribution: Lower edges of the Arid Transition from Sacra- 
mento Canyon and Mendocino County southward to the Cuiamaca 
Mountains, also in New Mexico and western Texas. 
Specimens examined: Cuiamaca Mountains, between Cuiamaca 
and Oriflamme Mines, Abrams 3924. 
z. PARKINSONIA. 
Rachis flattened, much-elongated; eae scattered. . P. aculeat 
Rachis terete; leaflets in distinct pai 2. P. ae. 
1. ParKINSONIA ACULEATA L. Sp. Pl. 375. 1753. 
Type locality: “Habitat in America calidiore.” 
Distribution: Valley of the Colorado River, northern Mexico 
and the lower Rio Grande; naturalized in the West Indies and 
the tropics of both hemispheres. Lower Sonoran and Tropical. 
Specimens examined: I have not seen any specimens from 
southern California. 
2. PARKINSONIA MICROPHYLLA Torr. Pacif. R. Rep. 4: 82. 1857. 
Type locality: “Banks of the Colorado [where it was collected 
by Mr. Schott near Fort Yuma] and on Williams River.” 
Distribution: Deserts of southern Arizona west to the Colorado 
Desert of southern California, and southward to adjacent Sonora 
and Lower California. Lower Sonoran. 
