KEY TO THE FAMILIES. 33. 



240. (Ill) Herbs with long stems and tendrils. Flowers uni- 



sexual, regular, or nearly so. Fruit a berry or gourd. 



145 CUCURBITACEAE. 

 Plants or flowers not as above. 24I. 



241. Ovules not distinct from placenta. Parasites on trees and 



shrubs. 37 LORANTHACEAE. 



Ovules distinct. Not parasites. 242. 



242. Mangrove trees with vivipary growing in brackish water. 



109 RHIZOPHORACEAE. 

 Not mangroves. 243. 



243. Ovary 1 celled, sometimes incompletely chambered. 244. 

 Ovary 2 or more celled, rarely 2 or more distinct ovaries. 250. 



244. Ovule 1. 116 UMBELLIFERAE. 

 Ovules 2 or more. 24S. 



245. Ovules basal or on a free central placenta. 246. 

 Ovules apical or on a parietal placenta. 248. 



246. Sepals 2. (Portulaca). 44 PORTULACACEAE. 

 Sepals 4—8. 247. 



247. Stamens numerous. Petals 5, ovules 2. Leaves alternate 



stipulate. 67 ROSACEAE. 



Stamens as many or twice as many as petals. 248a. 



248a. Leaves exstipulate. Stamens twice as many as petals. 



112 MELASTOMACEAE. 

 Leaves stipulate. Stamens as many as petals. (Pleurostylia). 



85 CELASTRACEAE. 



248. Ovules apical. Trees or shrubs. 110 COMBRETACEAE. 

 Ovules parietal. 249. 



249. Ovary inferior. Fleshy almost leafless plants. 



104 CACTACEAE. 

 Ovary half inferior. Leafy trees and shrubs. 



100 FLACOURTIACEAE. 



250. (243) Ovules solitary in each ovary cell. 251. 

 Ovules 2 or more in each ovary cell. 26I. 



251. Ovules erect or ascending. 252. 

 Ovules pendulous or descending. 254. 



252. Stamens 10 or more. 67 ROSACEAE. 

 Stamens 4 — 5. 253. 



253. Stamens alternating with petals. 85 CELASTRACEAE. 

 Stamens opposite petals. 92 RHAMNACEAE. 



254. Ovary 2 celled. 255 

 Ovary 3 or more celled. 26O. 



255. Style 1, stigma 1. Flowers 4-merous. 256. 

 Style with 2 — 4 stigmas or styles 2 — 3. 237. 



256. Flowers unisexual in cymes. Trees or shrubs, leaves opposite. 



(Cornus). 117 CORNACEAE. 

 Flowers hermaphrodite solitary. Herbs. (Trapa). 



113 OENOTHERACEAE. 



