PEA FAMILY 239 



Creek, e. Humboldt Co., Chesnut 4" Brew; Salt Creek, w. Tehama Co., Jepson; Grindstone Creek 

 near jet. Stony Creek, w. Glenn Co., Jepson 16,309 ; Asa Bean trail at crossing of Middle Eel 

 Eiver, s. Trinity Co., Jepson; Eound Valley, ne. Mendocino Co. (Contrib. U. S. Nat. Herb. 7 :356) ; 

 Hough Sprs., n. Lake Co., Jepson 9006; Cold Creek, Potter Valley, ace. Anson Blahe ; South 

 Mill Creek, Ukiah, Jepson 4005, 4009 ; Sonoma Geysers, Miyakma Eange, Bolander 3946 ; Middle- 

 town, Lake Co., ace. Anson Blake; Capay Valley, Yolo Co.; Putah Canon, Jepson 10,410; Pleas- 

 ant Valley, mv. Solano Co., Jepson 13,576; Miller Caiion, Vaca Mts., Jepson 13,581; Gates Canon, 

 Vaca Mts., Jepson 13,579. Marysville Buttes: South Peak summit, Jepson 13,580. Sierra Nevada: 

 McCloud Eiver, 6 mi. below Bartles, M. S. BaTcer ; lava beds, upper Fall Eiver Valley, Jepson; 

 Big Chico Creek, Butte Co., Heller 11,194; Eandolph Flat, Nevada Co., Jepson 13,578; Auburn, 

 M. E. P. Ames; lone, Braunton 1072; Jacksonville, Tuolumne Co., A. L. Grant 639; Mormon 

 Bar, Mariposa Co., Congdon; San Joaquin Eiver, Fresno Co. shore opp. Fish Creek, Jepson 

 12,879; Badger, Tulare Co., Woodhridge Metcalf (fls. white) ; Watson Spr., North Fork Kaweah 

 Eiver, Jepson 584; Grouse Valley, South Fork Kaweah Eiver, Jepson; Milo, North Fork Tula 

 Eiver, Jepson; Tehachapi Mts. ace. H. L. Bauer. S. Cal. : betw. Julian and Banner, Bay Bailey; 

 betw. Cuyamaca and Oriflamme mines, Abrams 3924. 



Eefs. — Cercis occidentalis Torr. ; Gray, Jour. Bost. Soc. Nat. Hist. 6:177 (1850), type 

 loc. "rocky plains of the upper Guadaloupe" (w. Tex.), Lindheimer; Jepson, Fl. W. Mid. Cal. 

 289 (1901), ed. 2, 215 (1911), Man. 511, fig. 509 (1925), C. nephrophylla Greene; Fedde, Eep. 

 Sp. Nov. 11 :111 (1912), type loc. San Diego Co., Palmer, Vasey. C. laUssima Greene, I.e., "moun- 

 tains of California", Geo. B. Grant. Siliquastrum occidentale Greene, Man. Eeg. S. F. Bay 

 84 (1894). 



4. PROSOPIS L. 



Deciduous shrubs or trees, the branches armed with spines or thorns. Leaves 

 deciduous, bipinnate with 1 pair (rarely 2 pairs) of pinnae ; leaflets in equal pairs, 

 numerous, small, entire. Flowers small, greenish-yellow, regular, sessile, in axil- 

 lary pedunculate cylindrical spikes. Calyx campanulate, with 5 short teeth, de- 

 ciduous. Petals 5, very much exceeding the calyx. Stamens 10, distinct, exserted. 

 Ovary stipitate, villous. Pod straight, curved or coiled, indehiscent, the many 

 seeds separated by thick spongy partitions. — Species about 25, tropical and sub- 

 tropical, all continents except Europe and Australia. (Greek prosopis, ancient 

 name for the Butter-bur.) 



Pinnae with 10 to 15 pairs of leaflets; thorns axillary, in pairs, singly or none; pod straight or 

 curving, compressed 1. P. juUflora. 



Pinnae with 5 to 8 pairs of leaflets ; spines in pairs, stipular ; pod spiraUy coiled into a straight 

 cylindric body 2. P. puhescens. 



1. P. juliflora DC. var. glandulosa Ckll. Honey Mesquite. Several-stemmed 

 or a short-trunked tree with crooked or arching branches forming a rounded or 

 depressed cro\^'n, 10 to 20 feet high ; leaflets linear, 1/2 to 1 inch long ; stipules linear 

 and membranous ; thorns 1 or 2, axillary, 14 to 1^2 inches long, or sometimes absent ; 

 flowers 2 lines long, condensed in slender cylindrical spikes mostly 2 to 3^ inches 

 long ; petals oblong, clawed, distinct ; stamens twice as long as the petals ; pods 

 borne in drooping clusters, 1 to 6 to each spike, linear, at first flat, later becoming 

 thickened, curved, 4 to 8 inches long, 4 to 5 lines broad, irregularly constricted 

 between the seeds which are about 3 lines long. 



Sandy or alkaline valleys and washes, 200 to 2100 feet: Death Valley region; 

 central and eastern Mohave Desert; Colorado Desert; local in the upper San Joa- 

 quin Valley, western Mohave Desert and in coastal Southern California. East 

 to Texas, south to northern Mexico. May-Oct. 



General habit. — The trunk nearly always branches at or very near the ground and produces 

 low rounded wide-spreading crowns. The individuals, though lacking height may, nevertheless, 

 attain large size. At the Eagle Springs in Death Valley one tree, measured in 1917, was 20 feet 

 high and 66 feet broad. Near Thousand Palms Canon, in the Conchilla Eange, a tree discovered 

 by us in 1914 had a height of 37 feet, a crown diameter of 114 feet and three sprawling trunks 

 arising from the base, the first 2 feet 5 inches in diameter at 2 feet, the second 1 foot 7 inches in 

 diameter at 3 feet, the third 1 foot 3 inches in diameter at 11/2 feet. Thus these trees, though 

 lacking stature, have a certain impressiveness on account of their very broad base. In the Palo 

 Verde Valley, where the tree is extremely common on the flats, the trunks are short (i/4 to 4 feet), 

 or as often branching widely at the very ground. In this valley in 1912 we measured a tree 18 



