STANDLEY — TREES AND SHRUBS OF MEXICO. 27 



Sepals 9 ; petals 6 ; leaves compound ; fruit 3-seeded. 



BERBERIDACEAE. 

 Ovules attached to a sutural placenta or to 2 or more parietal 

 placentae. 

 Ovules attached to the ventral suture of the ovary. Leaves 

 usually compound, alternate; fruit a legume. 



Corolla regular or nearly so CAESALPINIACEAE. 



Corolla veiy iiTegular, papilionaceous FABACEAE^ 



Ovules attached to 2 or more parietal placentae. 

 Calyx segments united. Leaves entire, small. 



ERANKENIACEAE. 

 Calyx segments distinct. 



Petals 4. Ovary stipitate CAPPARIDACEAE. 



Petals 5. 



Leaves pinnate MORINGACEAE. 



Leaves simple , VIOLACEAE. 



EE. Styles 2 or more, free or partially united, with separate stigmas, 

 or stigmas 2 or more and sessile. 

 Ovule 1. 



Sepals and petals each 3. Leaves entire, stipulate, the stipules 



sheathing POLYGONACEAE. 



Sepals and petals each 4 to 6. 



Stamens opposite the petals and of the same number ; style 



5-parted. Leaves simple PLUMBAGINACEAE. 



Stamens alternate with the petals, or more numerous ; styles 

 usually 3. Leaves usually compound-ANACARDIACEAE. 

 Ovules 2 or more. Leaves alternate. 



Plants with tendrils; ovary stipate PASSIFLORACEAE. 



Plants without tendrils ; ovary sessile. 



Leaves not scalelike TURNERACEAE. 



Leaves scalelike TAMARICACEAE. 



DD. Perfect stamens more than 10 

 Ovule 1. 



Leaves opposite CLUSLACEAE. 



Leaves alternate AMYGDALACEAE. 



Ovules 2 or more. 



Ovules basal, apical, central, or sutural. 



Petals and stamens hypogynous; sepals imbricate in bud. Leaves 



simple, alternate DILLENIACEAE. 



Petals and stamens perigynous, rarely almost hypogynous but the 

 sepals then valvate. 



Leaves estipulate, entire LYTHRACEAE. 



Leaves usually stipulate, dentate to pinnate. 



Ovules 2; leaves simple BOSACEAE. 



Ovules usually more than 2 ; leaves pinnate. 



CAESALPINIACEAE. 

 Ovules on several parietal placentae. 



Filaments wholly connate. Leaves alternate, estipulate, trans- 

 parent-dotted ; fruit berry-like CANELLACEAE. 



Filaments free or connate only at the base. 

 Leaves, at least the lowest, opposite, simple. Fruit a capsule ; 

 low shrubs. 



Plants not gland-dotted CISTACEAE. 



Plants gland-dotted HYPERICACEAE. 



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