PEA FAMILY 



237 



1. C. eriophylla Benth. Mock Mesquite. (Fig. 172.) Bush 1/2 to 2 feet 

 high ; leaves with (1 or) 2 to 4 pairs of pinnae ; pinnae with 9 to 12 pairs of leaflets ; 

 leaflets oblong, 1 to II/2 lines long ; stipules linear-lanceolate, somewhat indurated, 

 subpersistent ; calyx reddish-brown, turbinate, 5-toothed, the teeth triangular; 

 corolla dark red, cleft % the way down into oblong-ovate acute lobes; stamens 

 crimson, 9 to 11 Imes long, about 3 times as long as the corolla ; pods 2 inches long. 



Sandy washes and canons, 400 to 800 feet: 

 eastern Colorado Desert in the Chocolate Mts. 

 East to western Texas, south to Mexico and 

 Lower California. Mar.-May. 



Locs. — Calipatria (hills ne. of), Edith Boclcwell; 

 Mesquite Canon (Muhl. 7:77; Madrono 1:270) ; Ogilby 

 (6 mi. n.), Feirson 9788. 



Eefs. — Calliandra eriophylla Benth. Lond. Jour. 

 Bot. 3:105 (1844), type loc. Chila in district of Pueblo, 

 Mexico, Andrieux 405. AnnesUa eriophylla Britt. Trans. 

 N. Y. Acad. Sci. 14:32 (1894). Feuilleea eriophylla 

 Ktze. Rev. Gen. PI. 1:187 (1891). C.chamaedrys Engelm.; 

 Gray, Mem. Am. Acad. n. s. 4:39 (1849), type loc. Chi- 

 hualiua, Mex., Wislizenius, Gregg. 



2. ACACIA Willd. 



Trees or shrubs with bipinnate leaves and 

 small leaflets. Flowers minute, in ours yellow, 

 perfect or polygamous, condensed in peduncu- 

 late cylindrical or globular spikes. Spikes soli- 

 tary or fascicled in the axils or disposed in a 

 diffuse terminal panicle. Calyx 4 or 5-toothed. 

 Petals more or less united below. Stamens nu- 

 merous, distinct or nearly so, much exserted. 

 Pod 2-valved or indehiscent. — Species about 500, all continents but chiefly Aus- 

 tralia. (Greek akakie, from ake, a point, referring to the prickles.) 



1. A. greggii Gray. Catclaw. Straggling shrub 4 to 7 feet high, or some- 

 times becoming a small tree up to 15 feet high; branches armed with scattered 

 short but stout curved prickles, rarely unarmed ; leaves deciduous, 1 to 2 inches 

 long, with 1 or mostly 2 or 3 pairs of pinnae, each pinna with 4 to 6 pairs of pale 

 leaflets ; leaflets oblong or elliptic to oblong-obovate, 1 to 3^/2 lines long ; flowers in 

 cylindrical spikes % to 2^4 inches long; pods 2 to 11-seeded, much compressed, 

 more or less constricted between the seeds and curved or contorted, narrowed to 

 a cuneate base, 2 to 6 inches long, or sometimes much reduced, 1-seeded and simu- 

 lating a fry-pan in outline. 



Washes, valleys or hillsides, 200 to 2500 feet: Colorado Desert; north to the 

 Ord and Providence mountains in the Mohave Desert.^ East to Texas, south to 

 Mexico. Apr.-Oct. 



Habit note. — The trunk, encased in light brown bark roughly fissured into somewhat inter- 

 laced ribbon-like strands % to 1 inch wide, tends usually to part at or near the ground and pro- 

 duce long horizontally spreading or even trailing branches, with erect shoots. "While we were in 

 the Riverside Mts. along the Colorado River in 1912 an average individual 11 feet high with 

 crown diameter of 31 feet was measured, its branches having diameters of 4, 5, 6% and TVs 

 inches respectively. In the Palo Verde Valley a tree 19 feet high and 35 feet in cro^^^l diameter, 

 had four main limbs with diameters of 11, 11, 10%, 8% inches respectively. Another individual, 

 12 feet high and 30 feet in crown diameter, had a trunk 4 feet high and 17 inches in diameter at 

 one foot above the ground. In the beds of the washes on Ord Mt. occur individuals 6 to 16 feet 

 high with trimks 4 to 13 inches in diameter at one foot above the ground. Everywhere the indi- 

 viduals, on account of their reclining trunks, tend to cover more ground than any other desert 

 tree except the Honey Mesquite (Prosopis juliflora var. glandulosa CklL). Usually, throughout 



Pig. 172. Calliandra eriophylla 

 Benth. a, flowering branch, X % ; 

 b, long. sect, of fl., X 2; c, pod, X 

 1/2 ; d, seed, X 2. 



