FABACEAE. 187 



1. PROSOPIS L. 



Trees or shrubs often armed with axillary spines or 

 spinescent stipules. Leaves bipinnate with 1 or 2 pairs 

 of pinnae and usually numerous small entire leaflets. 

 Flowers greenish, regular, in cylindric or globose axillary 

 pedunculate spikes. Calyx campanulate, the teeth very 

 short and valvate. Petals 5, valvate, united below the 

 middle or at length free, woolly on the inner side. Sta- 

 mens 10, free and exserted; anthers tipped with a de- 

 ciduous gland. Ovary villous; style filiform. Pod linear, 

 compressed or nearly terete, straight, falcate or twisted, 

 coriaceous and indehiscent, usually pulp}^ within. 

 Seeds numerous, ovate, compressed. 



1. P. glandulosa Torr. (Algaroba or Mes quite.) A shrub 

 or small tree, much branched, the branches widely spreading; spines 

 axillary; petioles glabrous or sparsely puberulent; leaflets 8-12 pairs, 

 the pairs about 1 cm. distant, linear, 12-15 mm. long, 2.5-4.5 mm. 

 wide, sparsely puberulent at least on the margins; spikes nearly 

 sessile, 5-8 cm. long, usually dense; flowers very short-pedicelled, 

 2 mm. long; pods straight or slightly falcate, only 1-3 developing, 

 10-15 cm. long, 10-12 mm. wide, longitudinally veiny, on stipes 

 about 5 mm. long, straw-colored and sweetish when mature. 



River bottoms about San Bernardino. Common on the Colorado 

 Desert. 



2. STROMOBOCARPA Gray. 

 Distinguished from Prosopis by the tightly coiled pods. 



1. S. pubescens (Benth.) Gray. (Tornilla or Screw-bean.) 

 A shrub or small tree resembling the last in habit, more or less 

 puberulent; stipules spinescent; leaflets 5-8 pairs, the pairs 3-5 mm. 

 distant, oblong, 5-8 mm. long, obtuse at apex; spikes on peduncles 

 about 1 cm. long, 4-6 cm. long, often lax; flowers sessile, 3 mm. long, 

 pods usually several-many developing, twisted into a straight 

 cylinder, 25-35 mm. long, about 5 mm. broad, on stipes less than 

 2 mm. long. 



River bottoms about San Bernardino, growing with mesquite. 



Family 49. FABACEAE. Bean Family. 



Herbs, shrubs or trees with alternate stipulate com- 

 pound or rarely entire leaves and irregular or regular 

 flowers. Leaflets mostly entire, the upper sometimes 

 converted into tendrils. Calyx 4-5-lobed or 4-5-cleft, 

 its tube exceeding the perigynous disk, which bears the 



