KEY TO THE ORDERS. xxi 



Stamens 2. Order 41. OLEALES. 264 



Stamens more than 2. 



Ovule solitary in each carpel. 



Styles distinct ; ovule pendulous. 



Families in Order 28. GERANIALES. 217 

 Styles united ; ovule erect or ascending. 



Limnanthaceae in Order 31. SAPINDALES. 225 

 Ovules 2 or more in each carpel. 



Order 34. HYPERICALES. 231 

 tt Stamens inserted on the margin of a disk or hypanthium (peri- 



gynous or hypogynous). 

 Stamens as many as the petals and opposite them. 



Styles and upper part of the ovaries distinct ; ovules and seeds 



many. Saxifragaceae in Order 27. ROSALES. 170 



Styles united, ovules and seeds solitary or 2. 



Order 32. RHAMNALES. 227 



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

 Styles distinct ; upper part of the ovaries distinct, at least at 



maturity. Saxifragaceae in Order 27. ROSALES. 170 



Styles united. 



Hypanthium flat or obsolete : disk fleshy. 

 Plants without secreting glands in the bark. 



Order 31. SAPINDALES. 225 

 Plants with secreting glands in the bark. 



Rutaceaa in Order 28. GERANIALES. 221 



Hypanthium cup-shaped or campanulate : disk obsolete or in- 

 conspicuous. Order 37. MYRTALES. 240 

 b. Ovary inferior. 

 Stamens numerous. 



Hypanthium not produced beyond the ovary. 



Ovary partly inferior. Hydrangiaceae in Order 27. ROSALES. 170 

 Ovary wholly inferior. Order 35. OPUNTIALES. 234 



Hypanthium produced beyond the ovary. 



Families in Order 37. MYRTALES. 240 

 Stamens not more than twice as many as the petals. 

 Styles wanting ; stigmas sessile. 



Gunneraceae in Order 37. MYRTALES. 248 

 Styles present. 

 Styles distinct. 



Ovules several in each cavity of the ovary ; fruit a capsule 



or a fleshy many-seeded berry. 

 Fruit, if dehiscent, valvate. 



Families in Order 27. ROSALES. 169 

 Fruit circumscissile. 



Portulacaceas in Order 24. CHEXOPODIALES. 125 

 Ovules solitary in each cavity of the ovary ; fruit a drupe or 



2-5 more or less united achenes. Order 38. UMBELLALES. 249 

 Styles united, or single. 

 Plants without tendrils. 



Ovary enclosed in or surpassed by the hypanthium or ad- 



nate to it. 

 Ovules solitary in each cavity of the ovary. 



Order 38. UMBELLALES. 249 

 Ovules several in each cavity. 

 Ovary with parietal placentae. 



Loasaceae in Order 35. OPUNTIALES. 234 

 Ovary with central or basal placentae. 



Families in Order 37. MYRTALES. 240 

 Ovary exceeding the hypanthium, the top free. 



Hydrangiaceae in Order 27. ROSALES. 175 



