7^8 FLORA. 



i. Polypremum procumbens L. Tolypremum. (I. F. f. 2850.) Stems 

 tufted, somewhat rigid, 4-angled, 5-30 cm. long. Leaves 1-4 cm. loi g, 1^2 mm. 

 wide, acute, sessile, minutely rough-toothed on the margins, often with smaller 

 ones fascicled in their axil-; flowers solitary, sessile in the forks of the cymes and 

 along their branches, leafy-bracted; corolla 2 mm. long or less; capsule crusta- 

 ceous, didymous, about 2 mm. in diameter, slightly 2 lobed, the lol>es obtuse. In 

 dry sandy soil, N. J. and Penn. to Fla., Ky., the Ind. Terr, and Alex. Also in the 

 VV. Indies. May-Sept. 



Family 3. GENTIANACEAE Dumort. 



Gent 1 a 71 Fa m ily. 



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

 late entire leaves, reduced to scales in Bartonza, and regular perfect 

 flowers in clusters, or solitary at the ends of the stem or branches. 

 Calyx inferior, persistent, 4-12-lobed, -toothed or -divided (of 2 sepals in 

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

 gamopetalous, often marcescent, 4-12-lobed or -parted. Stamens as 

 many as the lobes of the corolla, alternate with them, inserted on the 

 tube or throat ; anthers 2-celled, longitudinally dehiscent. Disk none, 

 or inconspicuous. Ovary superior in our genera, 1 -celled or partly 

 2-celled; ovules numerous, anatropous or amphitropous ; stigma entire, 

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

 sperm fleshy, copious ; embryo small, terete or conic. About 65 genera 

 and 600 species, widely distributed. 



Leaves normal ; corolla-lobes convolute in the bud. 



Style filiform; anthers usually twisting or recurving when old. 



Corolla salverform. 1. Erythraea. 



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. 4. Gentiana. 



Corolla rotate. 5. I'leurogyne. 

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



Corolla rotate, a fringed gland at each lobe. 6. Frasera. 



Corolla campanulate, spurred at the base. 7. Tetragonanthus. 

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



Calvx of 2 foliaceous spatulate sepals; upper leaves normal. 8. Obolaria. 



Calyx of 4 lanceolate sepals; leaves all reduced to scales. 9. Bartonia. 



1. ERYTHRAEA Neck. 



Herbs, mostly annual or biennial, with sessile or amplexicaul leaves, and pink 

 white or yellow flowers in cymes or spikes. Calyx tubular, 5~4dobed or -divided, 

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

 spreading, contorted, convolute in the bud. Stamens 5 or 4, inserted on the COrolla- 

 tube; liLum-nts short-filiform; anther- becoming spindly twisted. Ovary I -celled, 

 the placentae sometimes intruded; style filiform; stigma 2-lobed. Capsule 2-valved. 

 Seed-coat reticulated. [Greek, red. the color of the flowers in some species.] 

 About 25 species, natives of the Old World and western N. and S. Am. Besides 

 the following, about 8 others occur in the western U. S. 



Flowers spicate-racenlose. I. E. spicata. 

 Flowers cymose or cvmose-paniculate. 



d leaves tufted. 2. E. Centaurium. 

 No tuft of basal leaves. 



mose-paniculate, numerous. 3. E. pulchella. 



Flowers f< w, cymose; western species. 4. E. exaltata. 



t. Erythraea spicata (I- ) Pars. Spiked Centaury. (I. F. f. 2851.) 

 Glabrous erect, i. 5 4.5 dm. high. 1 long or lanceolate-oblong, sessile, 



obtusish, daspingi 1 4 cm. long; flowers pink, sessile, about 10 mm. long; tube 



