viii KEY TO THE FAMILIES. 



Ovary simple. 



Stamens hypogynous. RANUNCULACEAE, 102. 



Stamens perigynous. ROSACEAE, 130. 



Ovary compound. 



Ovary 1-celled with a central placenta. PORTULACACEAE, 92. 

 Ovary several-celled. NYMPHAEACEAE, 101. 



Calyx more or less coherent with the surface of the 



compound ovary. 

 Ovary more than 1-celled. 



Leaves alternate, with stipules. ROSACEAE, 130. 



Leaves opposite, without stipules. Philadelphus, 127. 



Ovary 1-celled. 



Placenta basal. PORTULACACEAE, 92. 



Placenta parietal. 



Plants fleshy, leafless or with minute 



leaves; petals many. CACTACEAE, 167. 



Plants rough-leaved; petals 5-10. LOASACEAE, 166. 



2. Stamens not more than twice as many as the petals. 



Stamens opposite the petals. 



Ovary 2-4-celled. RHAMNACEAE, 160. 



Ovary 1-celled. 



Anthers opening by uplifted valves. BERBERIDACEAE, 111. 



Anthers not opening by uplifted valves. PORTULACACEAE, 92. 



Stamens not opposite the petals. 

 Ovary wholly superior. 

 Ovaries two or more. 



Ovaries somewhat united at the base, 



separate above. 



Trees. ACERACEAE, 159. 



Herbs. SAXIFRAGACEAE, 125. 



Ovaries entirely separate. 



Stamens united with each other and 



with the stigma. ASCLEPIADACEAE, 195. 



Stamens free from each other and 



from the stigma. 

 Stamens hypogynous. 



Leaves not fleshy. RANUNCULACEAE, 102. 



Leaves thick and fleshy. CRASSULACEAE, 124. 



Stamens perigynous. 



Stamens just twice as many as 



the pistils. CRASSULACEAE, 124. 



Stamens not just twice as many 



as the pistils. 



Leaves without stipules. SAXIFRAGACEAE, 125. 

 Leaves with stipules. ROSACEAE, 130. 



Ovary only one. 



Ovary 3-5-lobed and beaked with a 



united style. GERANIACEAE, 154. 



Ovary not lobed and beaked. 



Ovary simple with 1 parietal placenta. LEGUMINOSAE, 142. 

 Ovary compound, as shown by the 

 number of cells, placentae, styles 

 or stigmas. 

 Ovary 1-celled. 



Corolla irregular. 



Stamens 6; petals 4. PAPAVERACEAE, 112. 



Stamens and petals 5. VIOLACEAE, 164. 



