KEY TO THE FAMILIES 



Calyx 5-toothed. 

 Calyx of 5 distinct sepals. 

 Leafless parasitic plants, with 

 yellowish herbage. 

 Ovary 3-celled; styles 3-cleft; 

 capsule 3-valved. 

 Ovary deeply 4-lobed, forming 4 1- 

 seeded nutlets. 

 Leaves alternate. 

 Leaves opposite. 

 Corolla scarious; ovary 2-4-celled. 



Corolla irregular. 



Ovary 1-2 -celled; ovules numerous. 



Ovary 1 -celled; parasitic plants without green 

 foliage. 



Ovary 2-celled; plants with green foliage. 

 Ovary 4-celled, with 1 ovule in each cell. 



Ovary not lobed. 



Ovary deeply 4-lobed, splitting into 4 nutlets. 



SOLANACEAE, 320. 

 CONVOLVULACEAE, 282. 



CUSCUTACEAE, 284. 



POLEMONIACEAE, 286. 



boraginaceae, 302. 

 Menthaceae, 310. 

 Plantaginaceae, 343. 



Orobanchaceae, 342. 

 Scrophulariaceae, 326. 



Verbenaceae, 309. 

 Menthaceae, 310. 



** Ovary inferior. 



Stamens distinct. 

 Leaves alternate. 

 Leaves opposite or whorled. 

 Ovary 1-celled. 



Stamens 1-3; slender spring annuals. 

 Stamens 2-4; stout late summer herbs. 

 Ovary 2-5-celled. 



Ovary 2-celled; flowers regular, minute; 



stems usually 4-angled. 

 Ovary 2-5-celled; flowers regular or ir- 

 regular. 

 Stamens united into a tube around the ovary. 

 Flowers not in heads. 



Stamens 3 ; flowers regular. 

 Stamens 5; flowers irregular. 

 Flowers in heads on a common receptacle, ligulate 

 or tubular. 



Campanulaceae, 353- 



Valerianaceae, 350. 



DiPSACEAE, 350. 



Rubiaceae, 345. 

 Caprifoliaceae, 347. 



Cucurbitaceae, 351. 

 Campanulaceae, 353- 



ASTERACEAE, 356. 



