342 Trees of Southern California. [zor 
trunk hardly a foot in diameter. Flowers often 8-10; pod viscid, 
rough hirsute, and with some tack-shaped glands. Dry washes 
of the Colorado Desert from Indio to the Colorado River. Mesquite 
Canon, etc. Larger and more abundant in Arizona. 
Parkinsonia aculeatal, ‘* Hills of the Colorado, near Ft. 
Yuma, Schott.” Torrey, Mex. Bound. 59. 
Parkinsonia microphylla Torr. ‘‘ Colorado River, near Ft. 
Yuma,” Torrey, 1.c. These two species of Southern Arizona 
have not been observed by recent collectors at the above station. 
Parkinsonia Torreyana Wats. Nigro tree, 15 feet high, 
trunk 10 inches in diameter. Fls. April. requent in d 
washes of the Colorado Desert pte per to the Colorado 
River; Indian Wells, 
Prosopis juliflora DC. Straggling tree 20 feet high, usually 
several stemmed from the base, or arborescent. In various kinds 
of soil, but indicating a damp subsoil, and attaining its greatest 
development in the desert. Fls. (at San Bernardino) May; Fr. 
September. Throughout the entire desert region, scattered, 
or rarely, as at Indio, forming groves. As a shrub extending 
as far west as San Bernardino, Temecula, aud San Diego. 
Prosopis pubescens Benth. Arborescent shrub, 15 feet high, 
with slender stem. Common, but less abundant than the last, 
through the desert region, usually growing in ravines or the 
borders of dry washes. Whitewater; Warm Springs, etc. 
Acacia Greggit Gray. Armed shrub 2-10 feet high, form- 
ing dense thickets of small extent, usually on dry hillsides. 
Western border of the Colorado desert at 2000-3000 feet altitude; 
San Gorgonio Pass; San Felipe. Also at Warner’s Hot Springs, 
within the intramontane district. 
Prunus emarginata Walp., var. moll’s Brewer. Arborescent, 
the slender stems 10-15 feet high, usually several clustered. 
Leaves and stipules glandular toothed, lower surface of leaves 
sparsely hirsute, peduncles and petioles tomentose with long, soft 
hairs. Fils. June. Rare. Border of streams in ravines, Bear 
Valley, 6ooo feet altitude, San Bernardino Mountains. : 
Prunus demissa Walp. Cerasus demissa Greene, Fl. Fr. 
1. Shrub 2-6 ft. high, on hillsides, often in open patches. 
