ILLUSTRATED FLORA. 



VOL. III. 



Family 15. GENTIANACEAE Dumort. Anal. Fam. 20. 1829. 



GENTIAN FAMILY 



Bitter mostly quite glabrous herbs, with opposite (rarely verticillate) exstipu- 

 late entire leaves, reduced to scales in Bartonia, and regular perfect flowers in 

 terminal or axillary clusters, or solitary at the ends of the stem or branches. 

 Calyx inferior, persistent, 4~i2-lobed, -toothed or -divided (of 2 sepals in Obo- 

 laria), the lobes imbricated or not meeting in the bud. Corolla gamopetalous, 

 funnelform, campanulate, club-shaped or rotate, often marcescent, 4 12-lobed or 

 -parted, the lobes convolute or imbricated in the bud. Stamens as many as the 

 lobes of the corolla, alternate with them, inserted on the tube or throat; anthers 

 2-celled, longitudinally dehiscent ; filaments filiform, or dilated at the base. Disk 

 none, or inconspicuous. Ovary superior in our genera, i -celled or partly 2-celled ; 

 ovules numerous, anatropous or amphitropous ; style simple, or none ; stigma entire, 

 or 2-lobed, or 2-cleft. Capsule mostly dehiscent by 2 valves. Seeds globose, 

 angular or compressed ; endosperm fleshy, copious ; embryo small, terete or conic. 



About 70 genera and 700 species, widely distributed, most abundant in temperate regions. 

 Leaves normal ; corolla-lobes convolute in the bud. 



Style filiform ; anthers usually twisting or recurving when old. 



Corolla salverform. i. Centaurium. 



Corolla rotate. 2. Sabbatia. 



Corolla campanulate-funnelform. 3. Eustoma. 



Style short, stout or none ; anthers remaining straight. 

 Corolla without nectariferous pits, glands or scales. 

 Corolla funnelform, campanulate or clavate. 



Corolla without plaits in the sinuses ; calyx without an interior membrane. 



4. Gentiana. 



Corolla with plaits in the sinuses ; calyx with an interior membrane. 5. Dasystephana 

 Corolla rotate. 6. Pleurogyna. 



1-2 nectariferous pits, glands or scales at the base of each corolla-lobe. 



Corolla rotate, a fringed gland at each lobe. 7. Frasera. 



Corolla campanulate, spurred at the base. 8. Halenia. 



Leaves, at least those of the stem, reduced to scales ; corolla-lobes imbricated in the bud. 



Calyx of 2 foliaceous spatulate sepals ; upper leaves normal. 9. Obolaria. 



Calyx of 4 lanceolate sepals; leaves all reduced to scales. 10. Bartonia. 



i. CENTAURIUM Hill. Brit. Herb. 62. 1756. 



[ERYTHRAEA Neck. Elem. 2: 10. 1/90.] 



Herbs, mostly annual or biennial, with sessile or amplexicaul leaves, and small or middle 

 sized, commonly numerous, pink, white or yellow flowers in cymes or spikes. Calyx tubular, 

 5-4-lobed or -divided, the lobes or segments narrow, keeled. Corolla salverform, S~4-lobed, 

 the tube long or short, the lobes spreading, contorted, convolute in the bud. Stamens 5 or 4, 

 inserted on the corolla-tube; filaments short-filiform; anthers linear or oblong, becoming 

 spirally twisted. Ovary i-celled, the placentae sometimes intruded; style filiform; stigma 

 2-lobed. Capsule oblong-ovoid or fusiform, 2-valved. Seed-coat reticulated. [Latin, 100 

 gold pieces, with reference to its supposed medicinal value.] 



About 25 species, natives of the Old World, western North and South America, and in the West 

 Indies. Besides the following, about 8 others occur in the western and southwestern parts of the 

 United States. Type species : Gentiana Centaurium L. 



Flowers spicate-racemose. i. C.spicatum. 



Flowers cymose or cymose-paniculate. 



Basal leaves tufted. 2. C. Centaurium. 



No tuft of basal leaves. 



Corolla-lobes iy 2 "-2y 2 " long. 



i 



