KEY TO THE ORDERS 



Stamens borne on the margin of a disc or hypanthium. 



ROSALES: 122. 

 Carpels several and united. 



Stamens borne at the base of the receptacle. 



Stamens numerous, more than twice as many as the petals. 

 Stamen filaments distinct. 

 Aquatics with floating leaves. Nymphaeaceae: 56. 



Terrestrial plants or if aquatic leaves not floating. 



RHOEODALES: 57. 

 Stamen filaments united. 



Filaments united into a tube around the styles. 



MALVALES: 89. 

 Filaments in several sets, not forming a tube. 



Trees. MALVALES: 89. 



Herbs or shrubs. GUTTIFERALES: 86. 



Stamens few, not more than twice as many as the petals. 

 Stamens as many as the petals and opposite them. 

 Flowers monoecious. Euphorbiaceae: 83. 



Flowers perfect. Portulaceae: 69. 



Stamens as many as the petals and alternate with them, 

 or more; often twice as many. 

 Stamens 6, rarely 2, petals 4. RHOEODALES: 57. 



Stamens as many as the petals or twice as many. 

 Ovary one celled. 

 Placentae central or basal. CARYOPHYLLALES: 64. 

 Placentae parietal. GUTTIFERALES: 86. 



Ovary several celled. 



Stamens not adnate to the gynoecium. 

 Filaments partly or wholly united. 



GERANIALES: 80. 

 Filaments distinct. 



Ovules numerous in each cavity of the ovary. 



ERICALES: 94. 

 Ovules few or solitary in each cavity of the 

 ovary. 

 Flowers regular. GERANIALES: 80. 



Flowers irregular. Aesculus: 154. 



Stamens adnate to the gynoecium. Asclepiadaceae: 107. 

 Stamens borne on the margin of a disk or hypanthium. 

 Stamens as many as the petals and opposite them. 



Styles distinct, ovules numerous. Heuchera: 142. 



Styles united, ovules 1 or 2 in each cavity of the ovary. 



CELESTRALES: 151. 

 Stamens as many as the petals and alternate with them or 

 more. 

 Hypanthium flat or obsolete, not enclosing the ovary. 

 Ovary one celled, fruit a small drupe. 



Anacardiaceae: 154. 

 Ovary 2-several celled, fruit a dehiscent pod or capsule. 



CELESTRALES: 151. 

 Hypanthium enclosing the ovary but free from it. 



Lythraceae: 143. 



