KEY TO THE ORDERS ix 



Stamens inserted below the ovary. 



Families in Order Ranales. 131 

 Stamens inserted on the edge of a cup-shaped hypanthium. 



Rosaceae in Order Rosales. 157 

 Gynoecium of 2 or several united carpels : stigmas or styles 2 or 

 several. 

 Ovary, by abortion, i-celled and i-ovuled. 

 Leaves with sheathing stipules (ocreae). 



Order PoLYGONALES. 113 

 Leaves estipulate, or if stipules are present they are not sheath- 

 ing. 

 Trees or shrubs. 



Anthers opening by slits : ovary not seated in a hypan- 

 thium. Ulmaceae in Order Urticales. 108 

 Anthers opening by hinged valves : ovary seated in an 

 accrescent hypanthium. 



Lauraceae in Order Thymeleales. 219 

 Herbs or vines. 

 Leaves with stipules. 

 Stipules herbaceous : inflorescence spicate or racemose : 

 leaf-blades palmately veined. 



Cannabinaceae in Order Urticales. 108 

 Stipules scarious or hyaline : inflorescence cymose : 

 leaf-blades pinnatel}- veined. 



Families in Order Chenopodiales. 118 

 Leaves without stipules. 

 Stigmas entire. Order Chenopodiales. 118 



Stigmas 2-cleft. Euphorbiaceae in Order Geraxiales. 192 

 Ovary several-celled, or with several placentae, several-ovuled. 

 Stamens hypogynous, inserted under the gjmoecium in the 

 perfect flowers, not on a disk in the pistillate flowers. 

 Herbs. 



Flowers perfect. 

 Ovary several-celled. 

 Fruit baccate or nut-like, or a circumscissile capsule, 

 the carpels terminal on the receptacle. 



Families in Order Chenopodiales. 118 

 Fruit of several carpels lateral on the receptacle, each 

 carpel circumscissile. 



Penthoraceae in Order RoSALES. 157 

 Ovary 1-2-celled. 

 Stamens not tetradynamous, 4-8 : ovary i-celled. 



Order Chenopodiales. 118 

 Stamens tetradynamous : ovar5' 2-celled. 



Brassicaceae in Order Papaverales. 143 

 Flowers monoecious or dioecious. 

 Ovules with the raphe towards the axis of the gynoe- 

 cium. Euphorbiaceae in Order Geraniales. 192 

 Ovules with the raphe away from the axis of the gynoe- 

 cium. Buxaceae in Order Sapindales. 201 

 Trees or shrubs. 

 Gynoecium 5-carpellary, the carpels nearly distinct. 



Buettneriaceae in Order Malvales. 208 



