22 RUBIACE.E. 



ceUs. Style filiform, exserted : stigmas 2, obtuse. Drupe obovate, thin-fleshy, containing 

 2 cartilaginous plano-convex nutlets. Seed plano-convex. Embryo straight in fleshy albu- 

 men : cotyledons cordate, foliaceous : radicle inferior. Leaves fleshy-coriaceous, sessile. 

 * Tf * * Low herbs, with eutire and naked interpetiolar stipules : ovules erect, anatropous : 

 style filiform : stigmas filiform or linear. 



19. MITCHELLA. Flowers (3-6-) generally 4-merous, heterogone-dimorjjhous, geminate 

 at the summit of a peduncle and tlie o^■arics of the two connate. Calyx-teeth persistent. 

 Corolla between salverform and funnelform ; lobes valvate in the bud, upper face densely 

 villous-bearded within. Stamens inserted in the throat of corolla, with oblong authers, on 

 short filaments when the filiform style is exserted, on long exserted filaments when the style 

 and stigmas are included. Style-branches 4, hirsute-stigmatose down the inner side. Truit 

 a globular baccate syncarp, containing 8 compressed roundish cartilaginous nutlets (4 to each 

 flower). Albumen cartilaginous : embryo minute. Prostrate and creeping evergreen. 



20. KELLOGGIA. Flowers (-3-5-) generally 4-merous, singly slender-pedunculate. Calyx 

 with obovate tube and minute persistent teeth. Corolla between funnelform and salver- 

 form ; lobes naked, valvate in the bud. Stamens inserted in the tliroat of the coroUa, more 

 or less exserted : filaments flattened : anthers oblong-linear, fixed above the base. Style fili- 

 form, exserted : stigmas 2, linear-clavate, papillose-pubescent. Ovary 2-celled : ovules erect 

 from the base, anatropous. Fruit small, dry and coriaceous, beset with uncinate bristles, 

 separating at maturity into 2 closed carpels, which are conformed and adherent to the seed, 

 somewhat reniform in cross section. Embryo comparatively large, in fleshy albumen : coty- 

 ledons elliptical, as long as the radicle. 



***** Low herbs, with short-vaginate stipules setiferous or sometimes only 4-6-cus- 

 pidate : ovary 2-4-celled : solitary ovules borne on the septum and amphitropous : fruit 

 dry ; seed sulcate or excavated on the ventral face : embryo in corueous or firm-fleshy 

 albumen ; tlie radicle inferior : flowers small, sessile in terminal and axiUary glomerules : 

 corolla funnelform or salverform ; lobes valvate in tlie bud. 



-I— Fruit circumscissile, upper part with persistent calyx-limb falling off, exposing the seeds. 



21. MITRACARPUS. Flowers commonly 4-merous, capitate-glomerate. Calyx-lobes per- 

 sistent, unequal, the alternate pair mostly shorter or minute and stipule-like. Stamens in- 

 serted on the throat of the corolla. Short style-brauclies or stigmas 2. Fruit didymous, 

 membranaceous, 2-celled, a pyxidium, the upper half separating from the lower by transverse 

 circular dehiscence. Seed cruciately 4-lobed on the ventral side. 



■*— ■*— Fruit septicidal into its 2 to 4 component carpels : calyx-limb gamopliyllous at base 

 and circumscissile-deciduous as a whole at or before dehiscence : stamens borne on the 

 throat of the corolla. 



22. RIOHARDIA. Flowers (4-8-) commonly 5-6-raerous and 2-4-carpellary. Calyx-lobes 

 ovate-lanceolate or n.arrower. CoroUa funnelform. Stigmas 2 to 4, linear or spatnlate. 

 Carpels separating from apex to base, coriaceous, roughish, closed or nearly so; no per- 

 sistent axis. 



23. CRUSEA. Flowers (.3-5-) usually 4-merous and 2- (sometimes 3-4-) carpellary. Calyx- 

 lobes sul>nlate to triangular-lanceolate, sometimes Acry unequal or intermediate ones reduced 

 to smaU teetli. Corolla salverform to narrow funnelform. Stigmas 2 to 4, linear to spatn- 

 late-oval. Fruit 2-4-lobed, separating from a persistent axis into ohovoid m- globular charta- 

 ceous carpels, which either open at the commissure or sometimes remain closed. 



■I- -1- •*- Fruit septicidal at summit or throughout, its 2 or rarely 3 car]iels or valves bear- 

 ing persistent and quite or nearly distinct calyx-teeth. 



24. SPERMACOCE. Calyx-teeth, lobes of the short corolla, and stamens 4, or two of tlie 

 former sometimes abortive. Fruit small, from membranareons to tliin-crustaccous, one or 

 both the caipels opening ventrally to discharge the seed : no persistent carpophore, or some- 

 times a tliin dissepiment reniainijig, 



25. DIODIA. Caly.K-lobes (1 to 6) usually 2 or 4, distinct, distant. Corolla funnelform or 

 nearly salverform, with mostly 4-lol,ed limb, and stamens as manv, in.'^erted in its throat. 

 Style filiform, entire or 2-cleft : stigmas 2, Fruit somewhat tleshy-drupaceous or crustaceo- 

 eoriaceous, tardily separating through tlie dissepiment into 2 closed carpels: no car- 

 pophore. 



