156 PRACTICAL BOTANY. 



Calyx unequally 5-cleft, lower lobe longest. Pod 

 l-seeded. Stamens sometimes slightly monadelphous, the 5 

 alternate anthers often imperfect. Flowers spiked or ra- 

 cemed, white or mostly bluish-purple. Leaves 3- to 5-f olio- 

 late, often glandular-dotted. Psoralea. 



257. Leaves 3-foliolate 258 



Leaves with more than 3 leaflets, several or 

 many 260 



258. Pods curved or coiled. Flowers purple or yellow, 

 racemed or spiked. Stipules of ten toothed or slaslicd. 



Medicago. 

 Pods straight 259 



259. Flowers white or yellow, fragrant, in racemes. Le- 

 gume longer than the calyx, rugose. Melilotus. 



Flowers blue or violet, in spikes or racemes. Le- 

 gume as long as the calyx, or nearly so. Stipules cohering 

 with the petiole. Plants glandular-dotted. Half of the 

 anthers often somewhat imperfect 256 



Flowers yellow, in heads. Stipules <5vate 256 



260. Trees or shrubs, often with prickly spines for sti- 

 pules. Calyx slightly 2-lipped. Standard large and rounded, 

 turned back, scarcely longer than the other petals. Pod 1- 

 celled, compressed, elongated, many-seeded. Style bearded 

 inside. Flowers showy, white or rose-color, and sometimes 

 fragrant, in pendulous axillary racemes. Leaflets stipellate. 



Robiuia. 



Herbaceous or suffruticose plants. Calyx equally 



5-toothed or cleft. Flowers white or purplish, spiked or 



racemed .261 



261. Pod longitudinally 2-celled, more or less com- 

 pletely, by the turning inward of the dorsal suture. Stand- 

 ard small, its sides reflexed or spreading. Astragalus. 



Pod 1 -celled. Standard large, roundish, usually 

 silky outside. Plants villous, with long, silky, or rusty hairs. 



(239) Tephrosia. 



262. (80.) Stamens not more than 20 263 



Stamens usually more than 20 25 



