22 RUBIACE.E. 



cells. Style filiform, exserted : stigmas 2, obtuse. Drnpe obovate, thin-fleshy, containing 

 2 cartilaginous plano-convex nutlets. 8eed plano-convex. Embryo straight in fleshy albu- 

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

 * * * * Low herbs, with entire and naked interpetiolar stijjules: ovules erect, anatropous: 

 style filiform : stigmas filiform or linear. 



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

 at the summit of a peduncle and the ovaries 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 tlie throat of corolla, with oblong anthers, on 

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

 and stigmas are included. Style-branches 4, liirsute-stigmatose down the inner side. Fruit 

 a globular baccate syncarp, containing 8 compressed roundisli 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 tlie bud. Stamens inserted in the throat of the corolla, more 

 or less exserted : filaments flattened : anthers oblong-liuear, 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. Endiryo comparatively large, in fleshy albumen : coty- 

 ledons elliptical, as long as the radicle. 



***** Low herbs, with short-vagi n ate stipules setiferous or sometimes only 4-6-cus- 

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

 dry : seed sulcate or excavated on tlie ventral face : embryo in corneous or firm-fleshy 

 albumen ; the radicle inferior : flowers small, sessile in terminal and axillary glomerules ; 

 corolla funnelform or salverform ; lobes valvate in the bud. 



•f— Fruit circnniscissile, upper part with persistent calyx-limb falling off, exposing the seeds. 



21. MITRACARPUS. Flowers commonly 4-merous, capitate-glomerate. Cah^x-lobes per- 

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

 serted on the tiiroat of the corolla. Short style-branches 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 gamophyllous at base 

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

 throat of the corolla. 



22. RICHARDIA. Flowers (4-8-) commonly 5-6-merons and 2-4-carpellary. Calyx-lolies 

 ovate-lanceolate or narrower. Corolla funnelform. Stigmas 2 to 4, linear or spatulate. 

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

 sistent axis. 



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

 lobes subulate to triangular-lanceolate, sometimes very unequal or intermediate ones reduced 

 to small teeth. Corolla salverform to narrow funnelform. Stigmas 2 to 4, linear to spatu- 

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

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

 •}—-)—-)— Fruit septicidal at summit or throughout, its 2 or rarely 3 carpels 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 the 

 former sometimes abortive. Fruit small, from membranaceous to thin-crustaceous, one or 

 both the carpels opening vcntrally to discharge the seed : no persistent carpophore, or some- 

 times a thin di.ssepiment remaining. 



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

 nearly salverform, with mostly 4-lobed limb, and stamens as many, inserted in its throat. 

 Style filiform, entire or 2-(left : stigmas 2. Fruit somewhat fleshy-drupaceous or crustaceo- 

 coriaceous, tardily separating through the dissepiment into 2 closed carpels: no car- 

 pophore. 



