LEGUMINOS^ 



549 



between the 10-20 seeds, straight or falcate, contracted at the ends, 4'-9' 

 wide; seeds about \' long. 



A low tree, with a large thick taproot descending frequently to the depth of 40- 

 50, and furnished with radiating horizontal roots spreading in all directions and 

 forming a dense mat, a trunk 6'-8' in diameter, divided a short distance above 

 the ground into many irregularly arranged crooked branches forming a loose strag- 

 gling head, and slender branchlets at first pale yellow-green, turning darker in 

 their second year, furnished in the axils of the leaves of their first season with 

 short spur-like excrescences covered with chaffy scales, and armed with stout 

 straight terete supra-axillary persistent spines ^'-2' long, or rarely unarmed ; more 

 often a shrub, with numerous stems only a few feet high. Bark of the trunk thick, 

 dark reddish brown, divided by shallow fissures, the surface separating into short 

 thick scales. Wood heavy, close-grained, rich dark brown or sometimes red, with 

 thin clear yellow sapwood; almost indestructible in contact with the soil, and largely 

 used for fence-posts, railway-ties, the underpinnings of buildings, and occasionally 

 in the manufacture of furniture, the fellies of wheels, and the pavements of city 

 streets; the best fuel of the region, and largely made into charcoal. The ripe pods 

 supply Mexicans and Indians with a nutritious food, and are devoured by most 

 herbivorous animals. A gum, resembling gum-arabic, exudes from the stems. 



Distribution. Western Texas and eastern New Mexico, and on the island of 

 Jamaica ; eastward and westward diverging into two extreme forms. These are 



Prosopis juliflora, var. glandulosa, Sarg. 



Leaves with distant linear mostly acute glabrous dark green leaflets often 2' 

 long and \'-\' wide. Flowers with a usually glabrous calyx. 



A round-topped tree, often 20 high, with a trunk a foot in diameter, and long 

 gracefully drooping branches forming a symmetrical round-topped head. 



Distribution. Eastern Texas to southern Kansas, and southward into northern 

 Mexico. The common Mesquite of eastern Texas; reappearing with rather shorter 

 and more crowded leaflets in Arizona, southern California, and Lower California. 



