430 i'v><). (;en'tianaceae 



Ovary i-celled. Stigma 2-partite. — Species i. West Africa. Used 



medicinally. [Tribe HELIE.\K.J Schultesia Mart. 



Pollen-grains separate. [Tribe GENTIANEAE.j 5 



5. Ovary completely 2-celled. Pollen-grains very small 6 



Ovary i-celled, sometimes incompletely 2-celled. Pollen-grains rather 



large 9 



6. Anthers opening by terminal pores which are sometimes produced into 



sHts, without glands, exserted. Filaments inserted at the throat of the 

 corolla or somewhat lower. Corolla violet, pink, or white, with a short 

 and wide tube. Calyx winged. — Species 12. Tropics. Used as orna- 

 mental plants Exacum L. 



Anthers opening by longitudinal slits, nearly always with i — 4 small 

 glands at the base or the apex. Corolla yellow, with a more or less 

 elongated tube 7 



7. Anthers projecting beyond the corolla-tube. Filaments inserted in the 



sinuses between the corolla-lobes. — Species 80. South Africa and 



tropics. Some are used medicinally Sebaea R. Br. 



Anthers concealed within the corolla-tube. Filaments inserted in the corolla- 

 tube. Flowers 5-merous 8 



8. Filaments inserted in the lower part of the corolla-tube. Calyx not winged. 



Small plants with small flowers. — Species i. South Africa (Cape 



Colony). (Under Sebaea R. Br.) Lagenias E. Mey. 



Filaments inserted in the middle or the upper part of the corolla-tube, 

 Calyx winged. Flowers rather large. — Species 30. Tropical and 

 South Africa. {Parasia Rafin., including Exochaenium Griseb., under 

 Sehaea R. Br.) Belmontia E. Mey. 



9. Ovary divided into incomplete cells by the intrusion of the placentas. 



Stigma more or less distinctly 2-lobed. Stamens 5. 10 



Ovary completely one-celled with little intruding placentas 12 



10. Anthers more or less twisted after flowering. Pollen-grains smooth. — 



Species 6. North Africa and northern Central Africa. Used as medicinal 



or ornamental plants Erythraea L. C. Rich. 



Anthers erect or bent back after flowering. Pollen-grains tubercled or 

 netted. Calyx with small scales on the inside ii 



11. Corolla yellow ; tube short, glabrous within. Anthers exserted. Pollen- 



grains tubercled. Leaves stem-clasping. Flowers in many-flowered 

 panicles with large bracts. — Species i. Canary Islands. 



Ixanthus Griseb. 



Corolla white or red ; tube long, with 5 small scales on the inside. Anthers 



included. Pollen-grains netted. Flowers sohtary or in few-flowered 



cymes. — Species 9. Madagascar. Some are poisonous or are used in 



medicine Tachiadenus Griseb. 



12. Corolla with i — 2 glandular nectaries at the base of each segment ; tube 



very short. Stamens 4 — 5. Pollen-grains tubercled. — Species 35. 

 Tropica] and South Africa. Some are used medicinally. Sweertia L 



