Key to the Families xi 



Ovary 1, not lobed. 

 Ovary 1-celled. 



Leaves opposite, entire. GENTIANACEAE, 303. 



Leaves mostly alternate and seldom entire. 



HYDBOPHYLLACEAE, 319. 

 Ovary 2-celled; corolla not scarious. 

 Leafy plants. 



Calyx 5-toothed. SOLANACEAE, 349. 



Sepals 5, distinct. CONVOLVULACEAE, 307, 452. 



Leafless parasitic plants; herbage yellowish. 



CUSCUTACEAE, 310. 



Ovary 3-celled; styles 3-cleft; capsule 3-valved. 



POLEMONIACEAE, 311. 



Ovary 2-4-celled; corolla scarious. PLANTAGINACEAE, 375. 

 Ovary 1, deeply 4-lobed, forming 4 nutlets. 



Leaves alternate. BOBAGINACEAE, 328. 



Leaves opposite. MENTHA, 348. 



Corolla irregular. 

 Stamens 4 or 2. 



Ovary 1-celled; parasitic plants. OBOBANCHACEAE, 373. 



Ovary 2-celled. SCBOPHULABIACEAE, 355. 



Ovary 4-celled, not lobed, splitting into 4 nutlets. 



VEBBENACEAE, 336. 



Ovary 4-lobed, splitting into 4 nutlets. LABIATAE, 338. 



Stamens 5; ovary 2-celled. VEBBASCUM, 356. 



** Ovary inferior. 



Stamens distinct. 



Leaves alternate. CAMPANULACEAE, 385. 



Leaves opposite or whorled. 

 Ovary 1-celled. 



Stamens 1-3; slender spring annuals. VALEBIANACEAE, 382. 

 Stamens 2-4; stout late summer herbs. 



DlPSACEAE, 383. 



Ovary 2-5-celled. 



Ovary 2-celled; flowers regular, minute; stems usually 4-angled. 



RUBIACEAE, 377. 



Ovary 2-5-celled; flowers regular or irregular. 



CAPBIFOLIACEAE, 380. 



Stamens united into a tube around the ovary. 

 Flowers not in heads. 



Stamens 3; flowers regular. CUCUBBITACEAE, 384. 



Stamens 5; flowers irregular. CAMPANDLACEAE, 385. 



Flowers in heads on a common receptacle, ligulate or tubular. 



COMPOSITAE, 389. 



