KEY TO THE FAMILIES 7 



Calyx irregular, one of the 

 sepals spurred or saccate; 

 anthers united around the 

 stigma. 



69. BALSAMINACEAE 536 

 Calyx regular; none of the 



sepals saccate; anthers 

 distinct. 



Style basal, arising between 

 the nearly distinct lobes 

 of the ovary; leaves odd- 

 pinnate. 



70. LlMNANTHACEAE 537 



Styles not basal; leaves in 

 ours abruptly pinnate, or 

 digitate. 



71. ZYGOPHYLLACEAE 538 

 ** Stamens inserted on the margin of a disk or hypanthium (perigy- 



nous or hypogynous) . 

 Styles and upper part of the ovaries distinct. 



57. SAXIFRAGACEAE 376 

 Styles united. 



Stamens as many as the petals and opposite them. 



Fruit a samara. 78. ACERACEAE 551 



Fruit a berry, drupe, or capsule. 



Sepals manifest; petals involute; fruit capsular or dru- 

 paceous; ours shrubs or trees. 



79. RHAMNACEAE 553 



Sepals minute or obsolete; petals valvate; fruit a berry; 



ours vines with tendrils. 80. VITACEAE 556 



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



more. 

 Hypanthium flat or obsolete; disk fleshy. 



Styles united, arising in the center, between the nearly 

 distinct lobes of the ovary; small hydrophytic 

 plants. 70. LIMNANTHACEAE 537 



Styles not arising between the ovaries; trees or shrubs. 

 Plants without secreting glands in the bark. 



Plants with resiniferous tissue; fruit drupaceous; 

 seeds without aril; leaves in ours compound. 



77. ANACARDIACEAE 550 

 Plants without resiniferous tissue; fruit a loculic- 

 idal capsule; seed with a fleshy aril; leaves 

 simple. 76. CELASTRACEAE 548 



Plants with secreting glands in the bark. 



72. RUTACEAE 539 

 Hypanthium cup-shaped or campanulate; disk obsolete or 



inconspicuous. 90. LYTHRACEAE 582 



2. Ovary at least partly inferior. 



a. Stamens numerous. 



Ovary partly inferior. 



Fruit a capsule. 58. HYDRANGEACEAE 392 



Fruit a pome. 61. MALACEAE 445 



Ovary wholly inferior. 



Sepals and petals 4 or 5, very unlike each other; leaves ample. 



Trees or shrubs; fruit fleshy. 61. MALACEAE 445 



Herbs with rigid hairs; fruit capsular. 



87. LOASACEAE 569 



Sepals and petals nearly alike, at least the latter numerous; 

 leaves typically and in all ours mere scales or wanting; suc- 

 culent plants armed with spines. 88. CACTACEAE 575 



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



Styles wanting; stigmas sessile. 92. HALORIGIDACEAE 605 



Styles present. 



Plants without tendrils. 

 Styles distinct. 



Ovules several in each cavity of the ovary; fruit a cap- 

 sule or a fleshy many-seeded berry. 

 Fruit, if dehiscent, valvate. 



Leaves opposite; fruit a leathery capsule. 



58. HYDRANGEACEAE 392 

 Leaves alternate; fruit a berry. 



59. GROSSULARIACEAE 394 

 Fruit circumscissile. 42. PORTULACACEAE 262 



Ovules solitary in each cavity of the ovary; fruit a 



drupe or 2-5 more or less united achenes. 

 Fruit drupaceous or baccate; gynoecium 1-several- 

 carpellary, if 2-carpellary the stigmas introrse. 



