LEGUMINOS.E 



547 



on the outer surface ; stamens twice as long as the petals ; ovary coated with long 

 pale hairs. Fruit conspicuously thick-margined, 4/-14' long, long-stalked, tipped 

 with short straight or recurved points, 2 or 3 together on a common peduncle thick- 

 ened at the apex; seeds T Y long. 



A tree, 50-GO high, with a straight trunk 18'-2(y in diameter, separating 20-30 

 from the ground into slender spreading branches forming a loose round head, and 

 branchlets at first more or less striately grooved and thickly coated with pulverulent 

 caducous tomentum, becoming at the end of a few weeks terete, pale cinnamon-brown 

 and puberulous. Bark about \' thick, bright cinnamon-brown, and roughened by 



thick persistent scales. Wood heavy, hard, very close-grained, rich dark brown, 

 with thin clear yellow sap wood of 2 or 3 layers of annual growth; considered valu- 

 able and sometimes manufactured into lumber. 



Distribution. Rich moist soil of river banks and the borders of lagoons and small 

 streams; valley of the lower Rio Grande ; in Texas only for a few miles near its mouth ; 

 more abundant from Matamoras to Monterey in Nuevo Leon; and southward to the 

 neighborhood of the City of Mexico. 



Occasionally planted as a shade and ornamental tree in the towns of the lower Rio 

 Grande valley. 



5. PROSOPIS, L. Mesquite. 



Trees or shrubs, with branches without terminal buds and armed with geminate 

 supra-axillary persistent spines, and small obtuse axillary buds covered with acute 

 apiculate dark brown scales. Leaves alternate on branches of the year and fascicled 

 in earlier axils, deciduous, bipinnate, with many-foliolate piniue; petioles glandular at 

 the apex, with a minute gland, and tipped with the small spinescent rachis; stipules 

 linear, membranaceous or spinescent, deciduous. Flowers greenish white, sessile, in 

 axillary pedunculate spikes; calyx campanulate, 5-toothed, or slightly 5-lobed, de- 

 ciduous; petals 5, connate below the middle or ultimately free, glabrous ortomentose 

 on the inner surface toward the apex, sometimes puberulous on the outer surface; 

 stamens 10, free, inserted with the petals on the margin of a minute disk adnate to 

 the calyx-tube, those opposite the lobes of the calyx rather longer than the others; 

 filaments filiform; anthers oblong, versatile, their connective tipped with a minute 

 deciduous gland, the cells opening by marginal sutures; ovary stipitate, villose; 



