GENUS 6. 



MADDER FAMILY. 



257 



2. Diodia virginiana L. Larger Button- 

 weed. Fig. 3927. 



Diodia virginiana L. Sp. PI. 104. 1753. 



Hispid-pubescent or glabrate, much branched 

 from near the base, the branches procumbent 

 or ascending, i-2 long. Leaves lanceolate to 

 narrowly oval, narrowed at the base, acute, or 

 the lowest obtuse at the apex, i'-3' long; flow- 

 ers i or 2 in each axil, about 6" long, the 

 corolla-tube very slender ; fruit somewhat 

 fleshy, but becoming dry, hirsute or glabrous, 

 oval, 3"~4" high, furrowed, crowned with the 

 2 or 3 persistent lanceolate calyx-lobes. 



In moist soil, southern New Jersey to Florida, 

 west to Arkansas and Texas. June-Aug. 



7. GALIUM L. Sp. PL 105. 1753. 



Annual or perennial herbs, with 4-angled slender stems and branches, apparently verticil- 

 late leaves, and small white, green, yellow or purple flowers, mostly in axillary or terminal 

 cymes or panicles, the pedicels usually jointed with the calyx. Flowers perfect, or in some 

 species dioecious. Calyx-tube ovoid or globose, the limb minutely toothed, or none. Corolla 

 rotate, 4-lobed (rarely 3-lobed). Stamens 4, rarely 3; filaments short; anthers exserted. 

 Ovary 2-celled; ovules I in each cavity. Styles 2, short; stigmas capitate. Fruit didymous, 

 dry or fleshy, smooth, tuberculate, or hispid, separating into 2 indehiscent carpels, or some- 

 times only i of the carpels maturing. Seed convex oh the back, concave on the face, or 

 spherical and hollow; endosperm horny; embryo curved; cotyledons foliaceous. [Greek, 

 milk, from the use of G. verum for curdling.] 



About 250 species, of wide geographic distribution. Besides the following, some 35 others 

 occur in the southern and western parts of North America. The leaves are really opposite, the 

 intervening members of the ventricles being stipules. Type species : Galium Mollugo L. 



1. Fruit dry. 



A. Flowers yellow. i. G. verum. 



B. Flowers white, green or purple. 



i. Annuals. 



Flowers in axillary cymules, or panicled. 

 Fruit granular or tubercled, not bristly. 



Fruit slightly granular, or smooth, i mm. broad ; pedicels not recurved ; stem very slender. 



2. G. parisiense. 

 Fruit granular-tubercled, 3 mm. broad ; fruiting pedicels recurved ; stem stout. 



3. G. tricorne. 

 Fruit densely bristly-hispid. 



Cymes few-flowered ; leaves 2-8 cm. long ; fruit fully 4 mm. broad. 4. G. Aparine. 



Cymes mostly several-flowered ; leaves 1-2.5 cm. long ; fruit smaller. 5. G. Vaillantii. 

 Flowers solitary in the axils, subtended by 2 foliaceous bracts ; fruit bristly. 6. G. virgatum. 



2. Perennials. 



* Fruit bristly hispid. 



a. Leaves in 4's, i-nerved. 7. G. pilosum. 



b. Leaves in 4's, 3-nerved. 

 Leaves lanceolate, oval, or ovate ; flowers in open cymes. 



Upper leaves lanceolate to ovate-lanceolate, acuminate. 8. G. lanceolatum. 



Upper leaves ovate, oblong, oval, ovate-lanceolate or obovate, obtuse. 



Corolla usually hirsute ; plant mostly pubescent ; leaves oblong to ovate-lanceolate. 



9. G. circaezans. 



Corolla glabrous; plant little pubescent; some leaves obovate. 10. G. kamtschaticum. 



Leaves linear to lanceolate; flowers in terminal panicles. n. G. boreale. 



c. Leaves in 6's. 

 ** Fruit smooth or warty. 

 t Flowers brown-purple. 

 Leaves lanceolate, 3-nerved ; fruit smooth. 

 Leaves narrowly lanceolate, i-nerved; fruit warty. 



17 



12. G. triflorum. 



13. G. latifolium. 



14. G. arkansanum 



