RUBIACEJE. 165 



ORDER LV. R U B I A C E ^E . 



Our species herbs (Cephalanlhus and some species of Galium shrubby) 

 with opposite or verticillate mostly exstipulate entire leaves, and 4- 

 merous perfect (or often dioecious) flowers. Calyx-limb obsolete, or of 4 

 teeth. Stamens distinct, alternate with the corolla-lobes and inserted on 

 its throat or tube. Ovary 2 4-celled, with a solitary ovule in each cell. 

 Fruit indehiscent, dry or baccate. 



1. CEPHALANTHUS, Linn. (BUTTON-BUSH). Shrubs with oppo- 

 site or ternate leaves, and flowers in dense globose terminal and axillary 

 peduncled heads. Calyx inverse-pyramidal, 5-toothed. Corolla with 

 long slender tube and small 4-cleft limb. Stamens 4, short, on the 

 throat of the corolla. Style slender, long-exserted; stigma capitate; 

 ovary 2-celled. Fruit achene-like, 1 2 -seeded. 



1. C. occidentalis, L. Shrub or small tree, with ovate -lanceolate 

 leaves 35 in. long, rather glossy above, often more or less pubescent: 

 fl. white, in heads 1 in. thick, these solitary or few or several toward the 

 ends of the branches. River banks of the interior, especially of the 

 lower Sacramento and San Joaquin. June August. 



2. SHERARDIA, Dillenius. Annual, slender, rough, with angular 

 stem, and exstipulate leaves in verticels of 6. Flowers umbellate. Calyx- 

 limb of 46 accrescent teeth. Corolla salverform, with a slender tube 

 and 4-cleft limb. Stamens 4. Fruit of 2 dry indehiscent 1-seeded car- 

 pels, crowned by the calyx-teeth, separating when ripe. 



1. S. ARVENSIS, L. About 3 6 in. high, hispidulous-roughened or 

 nearly glabrous: leaves obovate-lanceolate, acute: fl. in small subsessile 

 umbellate cymes : corolla bluish. Berkeley. 



3. GALIUM, Diosc. (BEDSTRAW. CLEAVERS). Herbaceous or suffru- 

 tescent, with slender angular stems, verticillate leaves without stipules, 

 and small cymose flowers. Calyx-limb obsolete. Corolla rotate, 4-parted. 

 Stamens as many as the corolla-lobes, short. Styles 2, short: stigmas 

 capitate: ovary 2-lobed, 2-celled, 2-ovuled. Fruit didymous (biglobular), 

 dry or fleshy, separating into 2 close 1-seeded carpels which are inde- 

 hiscent, and glabrous, hispid, or hirsute. 



* Fruit dry when ripe. 

 H Annuals. 



1. G. SPURIUM, L. Branching chiefly from the base; diffuse, 12 ft. 

 high, glabrous except the retrorsely scabrous angles of the stem and 

 veins and margins of the leaves: leaves 68 in the whorl, linear-oblan- 

 ceolate, cuspidate: fl. 3-9 in axillary umbellate cymes; corolla pale 

 green, the segments acuminate: pedicels recurved after flowering: fruit 



