24 ANALYTICAL KEY. 



Stamens separate, inserted on the corolla, 



One to three, always fewer than the corolla-lobes. Yalerianace^, 228 

 'Four or five ; leaves opposite or Avhorled. 



Ovary 1-celled; flowers in a dense involucrate head. Dipsace^e, 229 

 Ovary 2 - 5-celled. 



Leaves whorled and without stipules. ) Rubiace^ 222 



Leaves opposite or whorled, and with stipules. ) 

 Leaves opposite without stipules (petioles some- 

 times with stipule-like appendages). . CAPRIFOLIACEiE, 216 



2, Ovaj-y free from the calyx {superior). 

 * Corolla irregular: stainens {ivith anthers) 4 and didynamous, or only 2. 

 Ovules and seeds solitary in the (1 -4) cells. 



Ovary 4-lobed, the style rising from between the lobes. Labiate, 403 



Ovary not lobed, the style from its apex. . . VEKBENACK.a;, 401 



Ovules numerous or at least as many as 2 in each cell. 

 Ovary and pod 1-celled, 



With a free central placenta ; stamens 2. . Lentibulace^, 395 



With 2 or more parietal very many -seeded placentas ; 



stamens 4 Orobanchace^, 393 



Ovary and fruit more or less 4 - 5-celled. . . . Pedaliace^, 399 

 Ovary and pod 2-celled, but the 2 placentae parietal. Bignoniace^, 398 

 Ovary and pod 2-celled ; placentae in the axis. 



Seeds rarely few, not on hooks, with albumen. Scrophulariace^, 377 

 Seeds few, borne on hook-like or other projections 



of the placentae : no albumen. . . . Acanthace^, 399 



* * Corolla someichat irregular : stamens {with anthers) 5. 

 Stamens free from the corolla ; anthers with their cells opening by 



a hole or chink at the top. Rhododendron, in Ericace^, 320 



Stamens inserted on the corolla. 



Ovary deeply 4-lobed around the style. Echium, in Borraginace^, 367 

 Ovary not lobed; pod many-seeded. 



Filaments or some of them woolly. Verbascum, Scrophulariace^, 379 

 Filaments not woolly. . . . Hyoscyamus, SoLANACEiE, 376 



* * * Corolla regular. 

 •*- Stamens as many as the lobes of the corolla. 

 Ovaries 2, separate ; their 



Styles and stigmas also wholly separate. Dichondra, Convolvulace^, 368 

 Stigmas and sometimes styles united into one. 



Filaments distinct ; pollen in ordinary grains. . Apocynace^, 337 



Filaments monadelphous ; pollen in masses. . . Asclepiadace^, 338 

 Ovary one, but deeply 4-lobed around the style (or 2-lobed in Heliotropium). 



Leaves alternate Borraginaceje, 360 



Leaves opposite Mentha, in Labiate, 407 



Ovary one ; pod 2-lobed or 2-horned at -^he summit. Loganiace^, 345 



Ovary one ; not deeply lobed, 



One-celled, one-ovuled, becoming an achene. PLANTAGiNACE-a;, 422 



pmpERTT uBiunr 



N. C. State College 



