10 ^rEKRILL. 



KEY TO THE GENERA. 



]. Petals valvate; flowers regular : A. Mimosoideae 



J. Petals imbricate; -flowers irregular (nearlj' or quite regular in Gleditsia, trees 

 with branched spines). 



2. Flowers not papilionaceous, the upper petal interior B. Caesalpixioideae 



2. Flowers papilionaceous, the upper petal (standard) exterior. 



C. Papilioxatae 

 A. ;\[iMO.«;orDEAE. 

 ] . Calj'x-lobes valvate. 



2. Stamens manj% at least more than 10, or more than twice the number of 

 petals. 

 3. Filaments more or less connate (Ingeac). 



4. Endocarp not distinct from the pericarp and not forming individual 

 envelopes about the seeds. 

 5. Pods indehiscent, septate between the seeds. 



6. Pod turgid, about 5 cm wide, the sutures not thickened ; petals 

 adnata below to the stamina! tube, otherwise free.... 1. Seria7tthes 

 6. Pod scarcely turgid, spongy or fleshy, less than 2 cm wide, the 

 sutures thickened ; petals connate below into a tube. 



2. Enterolohiinn 

 5. Pods dehiscent or indehiscent, not septate between tlie seeds. 



6. Pods very strongly curved or twisted 3. Pithecolobium 



6. Pods straight, not curved or twisted 4. Albizzia 



4. Endocarp distinct and free from the pericarp, the latter not septate, the 

 former septate between the seeds and forming an individual envelope 



about each seed 5. Wallaceodendron 



3. Stamens free; inflorescence capitate (Acacieae) 6. Acacia 



2. Stamens as many as or double the number of petals. 

 3. Anthers not gland-tipped. 



4. Pods straight, flat, smooth, with continuous valves, dehiscing tlirough 



the sutures; erect trees : 7. Leucaena 



4. Pods slightly curved or nearly straight, somewhat aculeate, with always 

 persistent, indehiscent sutures; sufl"rutescent herbs or undershrubs. 



5. Pods subcylindric, 4-angled 8. Schrankia 



5. Pods flattened '. 9. .Mi7nosa 



3. Anthers gland-tipped. 



4. Seeds albuminous (Adenanthercac) ; erect trees or shrubs. 



5. Spiny shrubs or small trees; pods indehiscent 10. Prosopis 



5. spineless trees; pods dehiscent 11. Adenanthera 



4. Seeds exalbuminous {Piptadenieae) ; great climbers, usually tendril- 

 bearing, with very large pods and seeds 12. Entada 



1. t'alyx-lobes imbricate (Parkieae) ; very large trees with capitate inflorescence. 



13. Parkia 

 B. Caesalpixioiueae. 



1. Caly.x entire, or the' segments above the receptacle more or less united into 

 a toothed or lobed tube. 

 2. Leaves 2-pinnate; stamens 10 (Diniorphandrcae) . 



3. Erect, unarmed trees, with few, medium to large leaflets; flowers small; 



pods woody, not winged 14. Erythrophloeum 



3. Scandcnt, usually armed shrubs, with many, usually small leaflets ; flowers 

 nil iliinii^ized; pods thin, winged down one suture (Eucacsalpinioideae) . 



28. Mezoneurum 



