250 



RUBIACEAE. 



VOL. III. 



2. LITTORELLA L. Mant. 2 : 295. 1771. 



A low perennial succulent herb, with linear entire basal leaves and monoecious flowers, 

 the staminate solitary or two together at the summits of slender scapes, the pistillate sessile 

 among the leaves. Sepals 4 Corolla of the staminate flowers with a somewhat urceolate 

 tube, and a spreading 4-lobed limb. Corolla of the pistillate flowers urn-shaped, 3-4-toothed. 

 Staminate flowers with 4 long-exserted stamens, their filaments filiform, the anthers ovate. 

 Pistillate flowers with a single ovary and a long-exserted filiform style. Fruit an indehiscent 

 i-seeded nutlet. [Latin, shore.] 



Two known species, the following typical, the other in southern South America. 



i. Littorella uniflora (L.) Ascherson. Plan- 

 tain Shore-weed. Shore-grass. Fig. 3911. 



Plantago uniflora L. Sp. PI. 115. 1753. 

 Littorella lacustris L. Mant. 2: 295. 1771. 

 Littorella uniflora Ascherson, Fl. Brand. 544. 1864. 



Tufted, usually growing in mats; leaves bright 

 green, i'-3' long, \"-\" wide, spreading or ascending, 

 mostly longer than the scapes of the staminate flow- 

 ers, which bear a small bract at about the middle; 

 sepals lanceolate, mostly obtuse, with a dark green 

 midrib and lighter margins, sometimes only 3 in the 

 fertile flowers ; stamens conspicuous, 4"-6" long ; 

 corolla-lobes ovate, subacute; pistillate flowers very 

 small; nutlet about i" long. 



Borders of lakes and ponds, Maine and Vermont to 

 Minnesota, Newfoundland, Nova Scotia and Ontario. 

 July- Aug. 



Family 36. RUBIACEAE B. Juss. Hort. 



Trian. 1759. 



MADDER FAMILY. 



Herbs, shrubs, or trees, with simple, opposite or sometimes verticillate, mostly 

 stipulate leaves, and perfect, often dimorphous or trimorphous, regular and nearly 

 symmetrical flowers. Calyx-tube adnate to the ovary, its limb various Corolla 

 gamopetalous, funnelform, club-shaped, campanulate, or rotate, 4~5-lobed, often 

 pubescent within. Stamens as many as the lobes of the corolla and alternate with 

 them, inserted on its tube or throat ; anthers mostly linear-oblong. Ovary i 10- 

 celled; style short or elongated, simple or lobed; ovules i oo in each cavity. Fruit 

 a capsule, berry, or drupe. Seeds various ; seed-coat membranous or crustaceous ; 

 endosperm fleshy or horny (wanting in some exotic genera) ; cotyledons ovate, 

 cordate, or foliaceous. 



About 340 genera and about 6000 species, of very wide geographic distribution, most abundant 

 in tropical regions. Known as Madderworts. 



* Leaves opposite, stipulate (sometimes verticillate in No. 3). 

 Ovules numerous in each cavity of the ovary ; herbs. 



Top of the capsule free from the calyx ; seeds few, peltate. 

 Capsule wholly adnate to the calyx ; seeds minute, angular. 

 Ovules i in each cavity of the ovary. 



Shrubs or small trees ; flowers in dense globular heads. 



Low evergreen herbs ; flowers 2 together, their ovaries united. 



Herbs ; flowers axillary, nearly sessile, distinct. 



Capsule separating into 2 carpels, one dehiscent, the other indehiscent. 

 Capsule separating into 2 (or 3) indehiscent carpels. 

 ** Leaves appearing verticillate; herbs (some of the leaves rarely opposite in No. 7); 



ovule i in each cavity of the ovary. 



Corolla rotate; calyx teeth minute or none. 7. Galium. 



Corolla funnelform. 



Flowers in involucrate heads. 8. Sherardia. 



Flowers in panicles. 4st>erula. 



i. HOUSTONIA L. Sp. PI. 105. 1753. 



Erect or diffuse, usually tufted herbs, with opposite entire often ciliate leaves, and small 

 blue purple or white, mostly dimorphous flowers. Calyx-tube globose or ovoid, 4-lobed, the 

 lobes distant. Corolla funnelform or salver form, 4-lobed, the lobes valvate, the throat glabrous 

 or pubescent. Stamens 4, inserted on the tube or throat of the corolla; anthers linear or 

 oblong. Ovary 2-celled. Style slender; ovules numerous in each cavity; stigmas 2, linear. 

 Capsule partly inferior, globose-didymous, or emarginate at the apex, loculicidally dehiscent 

 above, its summit free from the calyx. Seeds few or several in each cavity, peltate, more 



1. Houstonia. 



2. Oldenlandia. 



3. Cephalanthus. 



4. Mitchella. 



Spermacoce. 

 Diodia. 



