ioS 



RUBIACEAE, the Madder Family 



Herbs or shrubs, with opposite or whorled leaves and regular 

 flowers; sepals 4, or minute or almost wanting; petals 4, united; 

 stamens 4; ovary inferior. 



la. Shrub (1 3 m. tall; flowers white, in spherical heads, summer) 



Button Bush, Cephalanthus occidentalis. 



la. Herbaceous 2. 



2a. Leaves opposite 3. 



2b. Leaves whorled; flowers white, green, or purple (Bedstraw) 



6. 

 2c. Leaves whorled; flowers yellow Bedstraw, Galium verum. 



3a. Leaves about as long as wide (trailing; flowers paired, white, 

 in spring) Partridge Berry, Mitchella repens. 



3b. Leaves at least twice as long as wide 4. 



4a. Corolla salver-form, about 1 cm. wide; peduncles 1-flowered 

 (about 1 dm. high; flowers blue or white, in spring) 



Bluets, Houstonia coerulea. 



4b. Corolla funnel-form, about 5 mm. wide; flowers in clusters 

 (1 2 dm. high; flowers white or pale-purple, summer) (Hous- 

 tonia) 5. 



5a. Basal leaves strongly ciliate Houstonia, Houstonia ciliolata. 



5b. Basal leaves smooth Houstonia, Houstonia longlfolia. 



6a. Leaves in whorls of 4 7. 

 6b. Leaves in whorls of 6 8 16. 



7a. Ovary and fruit hispid with hooked bristles (3 7 dm. high; sum- 

 mer) 8. 

 7b. Ovary and fruit not bristly (early summer) 11. 



8a. Leaves with 1 principal vein (flowers dull purple) 



Bedstraw, Galium pilosum. 

 8b. Leaves with 3 principal veins 9. 



9a. Flowers bright-white Bedstraw, Galium boreale. 



9b. Flowers greenish, yellowish, or purplish 10. 



lOa. Leaves acuminate Bedstraw, Galium lanceolatum. 



lOb. Leaves acute or obtuse Bedstraw, Galium circaezans. 

 lla. Corolla-lobes 3 (26 dm. high; flowers white or greenish) 12. 

 lib. Corolla-lobes 4 13. 



12a. Flowers in clusters of 2 or 3 Bedstraw, Galium claytoni. 

 12b. Flowers solitary in the axils, on long hair-like pedicels 



Bedstraw, Galium trifidum. 

 13a. Corolla brownish or purple (36 dm. high) 



Bedstraw, Galium latifolium. 

 13b. Corolla white (14 dm. high) 14. 



14a. Flowers rather numerous in small cymes 



Bedstraw, Galium palustre. 

 14b. Flowers in- clusters of 2 or 3, or solitary 15. 



