330 GENTIANACEAE. 



with smaller ones fascicled in their axils; flowers solitary, sessile in the forks 

 of the cymes and along their branches, leaf y-bracted ; corolla 2 mm. long or 

 less; capsule crustaceous, didymous, about 2 mm. in diameter, slightly 2-lobed, 

 the lobes obtuse. 



Scrub-lands, Inagua at Matthew Town : New Jersey to Kentucky, Florida, 

 Mexico and Colombia ; Cuba ; Jamaica. POLYPREMUM. 



Family 3. GENTIANACEAE Dumort. 

 GENTIAN FAMILY. 



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

 late entire leaves, reduced to scales in Leiphaimos, 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 Obolaria), 

 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, anat- 

 ropous or amphitropous; stigma entire, or 2-lobed, or 2-cleft. Capsule 

 mostly dehiscent by 2 valves. 'Endosperm fleshy, copious; embryo small, 

 terete or conic, About 70 genera and 700 species, widely distributed. 



Corolla-lobes convolute in the bud ; leaves broad or narrow. 

 Stigmas roundish, much shorter than the style. 



Corolla-tube surpassing the calyx. 1. Centaurium. 



Corolla-tube much shorter than the calyx. 2. Eustoma. 



Stigmas linear or nearly so, about as long as the style. 3. Sabbatia. 



Corolla-lobes imbricated in the bud ; leaves reduced to scales. 4. Leiphaimos. 



1. CENTAUEIUM Hill, Brit. Herbal 62. 1756. 



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

 pink white or yellow flowers in cymes or spikes. Calyx tubular, 5-4-lobed 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; filaments short -filiform; anthers becoming spirally twisted. 

 Ovary 1-celled, the placentae sometimes intruded; style filiform; stigma 2-lobed. 

 Capsule 2-valved. Seed-coat reticulated. [Latin, 100 gold pieces, referring to 

 supposed medicinal value.] About 25 species, both in the Old World and the 

 New. Type species: Gentiana Centaurium L. 



1. Centaurium Brittdnii -Millsp. & Greenm. Field Mus. Bot. 2: 308. 1909. 



Annual, glabrous, much-branched, 5-18 cm. high, the branches very slender, 

 quadrangular. Basal and lower leaves obtuse or oblong-spatulate ; upper leaves 

 sessile, oblong-lanceolate to linear, acute, 1.8 cm. long or less; peduncles nearly 

 filiform, much longer than the upper leaves ; flowers white with a yellowish eye, 

 3-5-parted (mostly 4-parted) ; calyx 5-6 mm. long, its segments narrowly 

 linear, acute ; corolla 6-10 mm. long, its lobes oblong, about one-half as long as 

 the tube; capsule linear-elliptic, 6-8 mm. long. 



Dry sandy roadsides and sandy edge of marshes, Eleuthera, Watling's and 

 Great Exuma : Anegada. BRITTON'S CENTAUEY. 



