KEY TO THE OKDEKS ix 



Ovary 2-several-celled : placentae axile or central. 



Families In Order MALVALBS. 



Stamens with united filaments. . Order MALVALES. 



Stamens few, not over twice as many as the petals. 

 Stamens as many as the petals and opposite them. 



Buphorbiaceae in Order EUPHOBBIALES. 

 Stamens as many as the petals and alternate with them, or 



more, sometimes twice as many. 

 Stamens 6 : petals 4 : sepals 2 or 4. 



Families in Order PAPAVERALES. 

 Stamens, petals and sepals of the same number, or stamens 



more, usually twice as many as the sepals or petals. 

 Ovary 1-celled. 



Ovules, or seeds, on basal or central placentae. 



Families in Order CHENOPODIALES. 

 Stamens -with free and distinct iilaments. 



Tamaricaceae in Order HYPEEICALES. 

 Stamens with partially united filaments and usu- 

 ally adnate to the corolla. 



Styracaceae in Order EBENALES. 

 Ovules or seeds on parietal placentae. 



Stamens with united filaments and no staminodia. 

 Families in Order MALVALES. 

 Stamens with distinct filaments. 



Families in Order HTPEHICALES. 

 Ovary several-celled. 



Stamens with wholly or partly united filaments. 



Families in Order GEEANIALES. 

 Stamens with distinct filaments. 

 Anthers opening by pores. 



Families in Order EEICALES. 

 Anthers opening by slits. 



Stigmas or styles distinct and cleft, or foli- 

 aceous, or united by pairs. 



Order EUPHORBIALES. 

 Stigmas or styles all distinct or all united, 



neither cleft nor foliaceous. 

 Stamens 2. Oleaceae in Order OLEALES. 

 Stamens more than 2. 



Leaves with compound blades. 



Families in Order GEBANIALES. 

 Leaves with simple blades. 



Ovule solitary in each carpel. 



Families in Order GERANIALES. 

 Ovules 2 or more in each carpel. 



Tiliaceae in Order MALVALES. 

 Stamens inserted on the margin of a disk or hypanthium (perigynous 



hypogynous). 

 ens fewer t 



Stamens fewer than the sepals or the petals. 



Hippocrateaceae in Order SAPINDALES. 

 Stamens as many as the sepals or the petals, or more. 

 Stamens as many as the petals and opposite them. 



Order RHAMNALES. 

 Stamens as many as the petals and alternate with them, or 



more or many. 

 Styles distinct. 



Upper part of the ovaries distinct, at least at maturity. 

 Iteaceae in Order ROSALES. 



Upper part of the ovaries united. Order SAPINDALES. 

 Styles united. 



Hypanthium flat or obsolete : disk fleshy. 



Plants without secreting glands in the bark. 



Order SAPINDALES. 

 Plants with secreting glands in the bark. 



Families in Order GERANIALES. 



Hypanthium cup-shaped or campanulate : disk obsolete 

 or inconspicuous. 



Order MYBTALES. 

 Ovary inferior. 



Stamens numerous. 



Styles distinct. Families in Order ROSALES. 



Styles united. 



Shrubs or trees, not succulents, sometimes woody vines. 

 Hypanthium not produced beyond the ovary. 



Hydrangeaceae in Order ROSALES. 

 Hypanthium produced beyond the ovary. 



Families in Order MTRTALES. 



Shrubs with partly succulent stems and branches and rudi- 

 mentary or obsolete leaves, usually spiny. 



Order OPUNTIALES. 



