ARTIFICIAL KEY TO THE NATURAL ORDERS. XXI 



* * Ovwry free from, the calyx {superior). 

 ■t- Flowers irregular. Ferfect stamens almost always less than 6. 

 Ovules and mostly the seeds numerous, or sometimes only 2, in each cell. 

 Pod 1-celled, with a free central placenta. Stamens 2. LENTIBULACIH^, 276 



Fodl-celled with 2- 4parietal placentae. Stamens 4. Leafless plants. OROBANCHACE^, 279 

 Pod falsely 2 - 5-celled : placentse parietal. Seeds without albumen. BIGNONIACE^, 277 

 Pod 2-celled with the placentse in the axis. 

 Seeds numerous, sometimes few, with copious albumen. SCKOPHnLARIACEiB, 281 



Seeds few in each cell, fiat, entirely destitute of albumen. ACANTHAGE.^, 296 



Ovules and seeds (4, rarely 1) one in each cell. 

 Ovary deeply 4-lobed ; the style rising from between the lobes. LABIATiE, 300 



Ovary not lobed ; the style terminal. YERBENAGEiG, 298 



•*- -f- Flowers regtdar; stamens as mmvy as the lobes of the corolla or calyx. 

 Ovary deeply divided around the single style into 4 one-ovuled lobes. BORRAOINACE^, 319 

 Ovary 1-celled, with the ovules or placentse parietal. 

 Leaves toothed or cut, often rough-hairy, petioled. HYDBOPHYLLAGE.^, 326 



Leaves entire, sessile and opposite, glabrous. i 



Leaves petioled, alternate, entire or with 3 entire leaflets. ) GENTIANACE^, 341 



Ovary2-10-ceUed. 

 Style none. Corolla deeply 4 -6-parted. Shrubs or trees. AQTJIPOLIACEa:, 263 



Style present. Plants with green herbage. 

 Stamens 4. Pod circumcissiie, and the partition loose. PLANTAGINAGE^, 263 



Stamens 5, nearly or quite free from the corolla. ERICAGE^, 245 



Stamens 5, borne on the corolla.. 

 Stipules present between the bases of opposite leaves. LOGANIE^, 174 



Stipules none. 

 Leaves opposite. Pod 2-ceIIed, with several winged seeds. OELSEMINEiB, 283 



Leaves opposite or alternate. Pod 3-celled, few-seeded. PQLEMONIACE^, 829 



Leaves alternate Pod or berry many -seeded. SOLANAGEJS, 338 



Leaves alternate. Pod 2 - 6~-seeded. ^ 



Style present. Plants destitute of green foliage. i CONYOLTULAGEai:, 332 



Ovaries 2, separate ; their styles and stigmas also separate. J 

 Ovaries 2, separate, but united at the top by a common stigma. 

 Filaments distinct : pollen powdery, in ordinary anthers. APOOYNACEJE, 349 



Filaments mostly monadelphous : pollen cohering in masses. ASCLEPIADACE^, 350 



•*- -I- -I- Flowers regular: statne-as fewer than the lobes of the corolla. 

 Low herbs. Pod circumcissiie, 4 - many-seeded : partition separating. PLANTAGINACEiE, 268 

 Shrubs. Drupe or berry 1 - 2-Beeded. OLEACEiB, 356 



Division III. APETALOUS : corolla (and sometimes the calyx) wanting. 



A* Flowers not in catkins. 



* Ovary or cells oftlie ovary containing many oimles. 



Ovary and pod 6-celled, inferior (calyx-tube adherent). ARISTOLOCHIACKaE, 359 



Ovary and pod 4-ceUed, inferior. Ludwigia in ONAORAGE^, 129 



Ovary and pod 3-5-celled, superior (calyx free). 

 Pod 6-beaked, opening across the beaks. Penthorum in GRASSnLACE.3S, 139 



Pod beakless, circumcissiie. Leaves fleshy. Sesuvium in PORTULACACEiE, 63 



Pod beakless, 3-valved. Leaves whorled. MOLLUGINEiE, 54 



Ovary 2-celled, superior. Flowers perfect, separate. 

 Calyx enclosing the thin (at length often 1-celled) pod. Ammannia in LYTHRAGE^, 127 

 Galyx none. Pod many-i^bbed. Aquatic herbs. PODOSTEMACEiE, 384 



Ovary 2-colled. Flowers imperfect, capitate. Uquidambar in HAMAMELAGE^, 148 



Oavry 1, compound, but only one-celled. 

 Placent« 2, parietal Ghrysosplenium m SAXIFRAGACE^, 141 



