24 ANALYTICAL KEY. 



Stamens separate, inserted on the corolla, 



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

 Four or five ; leaves opposite or whorled. 



Ovary 1 -celled; flowers in a dense involucrate head. DIPSACE^E, 229 

 Ovary 2 - 5-celled. 



Leaves whorled and without stipules. I RUBIACEJE 222 



Leaves opposite or whorled, and with stipules. ) 

 Leaves opposite without stipules (petioles some- 

 times with stipule-like appendages). . CAPRO-OLIACE^;, 216 



2. Ovary free from the calyx (superior). 

 * Corolla irregular: stamens (with 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. VERBENACE^, 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. . LENTIBULACEJS, 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 placenta? parietal. BIGNONIACEJE, 398 

 Ovary and pod 2-celled ; placenta? 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 somewhat 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 ERICACEAE, 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.E, 379 

 Filaments not woolly. . . . Hyoscyamus, SOLANACE.E, 376 



* * * Corolla regular. 



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

 Ovaries 2, separate ; their 



Styles and stigmas also wholly separate. Dichondra, CONVOLVULACE.E, 368 

 Stigmas and sometimes styles united into one. 



Filaments distinct ; pollen in ordinary grains. . APOCYNACEJS, 337 



Filaments monadelphous ; pollen in masses. . . ASCLEPIADACE^E, 338 

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



Leaves alternate BORRAGINACE.E, 360 



Leaves opposite. ...... Mentha, in LABIATE, 407 



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



Ovary one ; not deeply lobed, 

 One-celled, one-ovuled, becoming an achene. PLANTAGINACE^;, 422 



