171 



LEGUMINOS^ : J^ULSE FAMILY. 



37. — Locust. IRvhinia Reo-Mexicana, Gray.) 



Usually a small tree, 20 to 25 feet, with a diameter of 3 to G ioclies ; or 

 a shrub iiiuler 6 feet in height. It occurs in sonthorn Colorado, south- 

 western and western New Mexico (and in Arizona and southern Utah 

 between 4,500 and 7,000 feet elevation). It is said to reach its best de- 

 velopment in the valley of the Purgatoire Eiver, southeastern Colorado. 

 At high elevations often reduced to a shrub. The wood is heavy, very 

 hard, and strong. 



Description. — Leaves composed of from 4| to 9^ pairs of elliptical leaflets, wliicli arc 

 more or less clothed with a whitish silky down, especially promineut on very young 

 leaves. Leaf-stems and branchlets thickly set with stiff, straight, glaiidnlar hairs, as 

 also are the pods. The latter are flat, often jointed, and vary In length from I to Wi 

 inches, with a width of not more than ^ an inch ; the end of the pod terminates in a 

 curved awn. Two rather strong thorns J to i an inch long) at the base of each leaf- 

 stalk. Flowers showy, purplisho 



38. — Frigolito. [Sopliora seeundiflora, Lagasca.) 



Chiefly a shrub, forming dense' growths along streams or growing 

 sparingly on rocky hill sides ; as a tree it is seldom more than 30 feet 

 high, with a slender trunk. It extends from the mountains of New Mex- 

 ico to the Gulf coast of Texas, and where large enough to be available 

 its hard heavy wood is highly esteemed for fuel. Very ornamental in 

 appearance. 



Descrqytion. —LiQUYes compound, evergreen, with from to 5^ — scarcely opposite — 

 pairs of leaflets ; the latter I to 2| inches long and -} to 1 inch wide, elliptic-oblong 

 or ovate, with a wedge-shaped base and a usually rounded apex ; margin entire, 

 smooth, often shiny above; leaf-stems with a groove on top, and when young vel- 

 vety, as are the flower- stems. Pods thick, woody, silky, with 1 to 2 speherical or 

 elliptical (rarely 3 or 4 fertile) joints, which are f of an inch in diameter and contain 

 one or two red, very hard-shelled beans, bearing a deep white scar. They are said 

 to have produced poisonous effects in persons who have eaten them, although the 

 Angora goats feed upon the leaves of the plant and often swallow the beans without 

 injury; but the shells of the latter are rarely, if ever, crushed by the animal's teeth. 



39. — Mesquit. Algauoba. Honey-Pod. Honey Locust. (Pro- 



sopis jitl'ijlora, De Candolle.) 



A tree of great economic impox.^tance. It is found in southern Colo- 

 rado, and through New Mexico (to southern California ; occuriug also 

 in western Texas, southern Utah, and Nevada, Mexico, and southward). 

 Along streams and in valleys it sometimes forms forests of considerable 

 extent, though never attaining a height of more than 50 feet, with a 

 diameter of 1 to 2 J feet ; commonly much smaller, and in dry rocky situa- 

 tions, especially those subject to annual burning, reduced to a shrub j but 

 the root system is then enormously developed — locall}^ termed under- 



