CASSIACEAE 583 



lets 30-70, the blades oblong, 3-4 mm. long, obtuse or acutish, merely ciliolate, not prom- 

 inently nerved : stipules ovate : peduncles commonly shorter than the subtending bracts or 

 longer at maturity : spikes globose or nearly so, about 1 cm. in diameter : pods oblong, 

 2-3 cm. long, narrowed into stipes only 2-4 mm. long. 



In dry soil, southern Texas and tropical America. Spring to fall. 



3. Neptunia Lindheimeri Robinson. Stems branched at the base, the branches dif- 

 fuse, persistently pubescent, several dm. long : leaves with 6-10 pinnae, leaflets 30-60, 

 the blades conspicuously ciliate and pubescent on the lower surface, blunt or mucronulate : 

 peduncles becoming 2.5-6.5 cm. long: pods oblong and cuneate at the base, 2.5-3.8 cm. 

 long, permanently pubescent, the stipes 4-5 mm. long : seeds 3-10. 



On prairies, Texas. Spring and summer. 



4. Neptunia Floridana Small. Stems several from large roots, ascending or spread- 

 ing, 3-7 dm. long, sparingly pubescent or glabrate, commonly branching, more or less 

 roughish pubescent : leaves rather numerous, with 3-5 pairs of pinnae : stipules lanceo- 

 late, acuminate ; leaflets numerous, the blades oblong or narrowly oblong, 4-5.5 mm. long, 

 often mucronulate, ciliate, prominently 3-nerved, sessile : peduncles slender, much longer 

 than the subtending leaves : spikes oval or oblong, 1-1.5 cm. long: pods oblong, 2.5-3.5 

 cm. long, apiculate, rather lustrous, glabrous, the stipe 2-4 mm. long : seeds 5-10. 



In sand, Florida to Louisiana. Spring to fall. 



13. PROSOFIS L. 



Shrubs or trees, often armed with axillary spines. Leaves alternate : blades 2-pinnate, 

 with four pinnae : leaflets narrow, relatively few. Flowers perfect, in green or yellowish 

 cylindric spikes. Calyx 5-lobed, sessile. Corolla of 5 distinct or slightly united petals. 

 Stamens 10 : filaments distinct. Ovary often stipitate. Ovules numerous. Pods in lax 

 clusters, flattened, straight or slightly curved, indehiscent, the interior tissues more or 

 less spongy. 



1. Prosopis glandulosa Torr. A shrub or tree sometimes 15 m. tall, usually with 

 zigzag branches, mostly armed with thorn-like spines. Leaves with 2-4 pinnae, long- 

 petioled ; leaflets 12-60, the blades linear or nearly so, 1.5-4 cm. long, obtuse or acutish : 

 peduncles 5-10 mm. long : spikes 4-8 cm. long : calyx campanulate, about 1 mm. high ; 

 lobes triangular, slightly shorter than the tube : petals erect, linear or nearly so, 4-5 times 

 longer than the calyx, acute, pubescent within : stamens hardly twice as long as the petals : 

 ovary pubescent : pods linear, 1-2 dm. long, straight or nearly so : seeds oblong. 



In plains or prairies, Kansas to Texas, Arizona and Mexico. 



14. STROMBOCARPA A. Gray. 



Shrubs or trees, with axillary spines. Leaves alternate : blades 2-pinnate, short- 

 petioled or sessile, with few pinnae : leaflets relatively few. Flowers perfect, in cylindric 

 or globular spikes. Calyx 5-lobed, campanulate or turbinate. Corolla of 5 distinct or 

 slightly united petals. Stamens 10 : filaments distinct. Ovules numerous. Pods in dense 

 clusters, each tightly coiled into a spiral, woody without, pulpy within. 



1. Strombocarpa ciner^scens A. Gray. A low shrub, armed with slender spines. 

 Leaves with 2-4 pinnae, sessile or short-petioled ; leaflets 10-20, the blades crowded, 1.5-3 

 mm. long, obtuse, reticulated : peduncles 1-3 cm. long : heads globose, 1-1.5 cm. in 

 diameter : calyx turbinate, nearly 2 mm. high : petals linear, fully twice as long as the 

 calyx : pods 1.5-4 cm. long, spirally twisted into a cylinder 5-7 mm. thick. 



In moist soil, along or near the lower Rio Grande, southern Texas and Mexico. 



FAMILY 16. CASSIACEAE Link. SENNA FAMILY. 



Trees, shrubs or herbs, sometimes prickle- armed. Leaves alternate, usually 

 with stipules : blades simple or compound. Flowers mostly perfect, sometimes 

 polygamous, monoecious or dioecious, variously disposed, regular or irregular. 

 Calyx of 5 more or less united sepals. Corolla of usually 5 petals, imbricated, the 

 upper one enclosed by the lateral ones in the bud. Androecium of 10 stamens 

 or fewer. Filaments distinct or united. Gynoecium of a single carpel. Ovary 

 1-celled, sometimes stipitate. Style terminal. Ovules 1-many. Fruit a 

 legume, 2-valved or indehiscent. Seeds with or without endosperm. 



