GENTIAN FAMILY 355 



1. Eustoma exaltatum (L.) Griseb. Tall Eustoma. Fig. 3796. 



Gentiana exaltata L. Sp. PI. ed. 2. 331. 1762. 

 Lisianthus exaltatus Lam. Encycl. 3: 662. 1789. 

 Eustoma silenifolium Salisb. Parad. Lond. 1: pi. 34. 1806. 

 Chlora exaltata Griseb. Gen. & Sp. Gent. 118. 1839. 

 Eustoma exaltatum Griseb. in A. DC. Prod. 9:51. 184S. 



Annual or short-lived perennial, with a taproot, the stems solitary or sometimes 2-3, erect, 

 branched above, 3-7 dm. high, herbage glaucous. Basal leaves obovate to broadly spatulate, 

 narrowed below to a broad petiole, stem-leaves sessile, clasping and often slightly connate, 

 broadly to rather narrowly oblong, the lower obtuse, the upper acute, 2-5 cm. long, mostly 

 3-5-nerved, those of the inflorescence reduced to subulate bracts ; flowers in an open cymose 

 panicle; calyx-lobes subulate, 10-15 mm. long; corolla blue or often white, the tube about 1 cm. 

 long, the lobes oblong-obovate, 1 . 5-2 cm. long ; stigma-lobes oblong ; style 4-5 mm. long ; 

 capsule oblong-ellipsoid, 8-12 mm. long, very obtuse at apex. 



Along streams, Sonoran Zones; along the Santa Ana River in San Bernardino and Orange Counties, also in 

 the Colorado Desert at Thousand Palms, Palm Canyon, Mason Valley, and Westmoreland; east to Arizona, New 

 Mexico, Texas, and Florida, south to Lower California, central Mexico, and the West Indies. Type locality: "In 

 America." Jan.-Dec. 



4. GENTIANA [Tourn.] L. Sp. PI. 227. 1753. 



Erect annual or perennial, glabrous or puberulent herbs, with mostly sessile, opposite 

 or rarely verticillate leaves. Flowers solitary or clustered, terminal or axillary, showy, 

 blue, purple, white, or rarely yellow, calyx tubular, 4-7-cleft. Corolla tubular, campanu- 

 late, funnelform or salverform, 4-7-lobed, often with plaits produced into lobes or teeth 

 in the sinuses between the lobes. Stamens as many as the corolla-lobes and inserted 

 alternate with them, included ; anthers versatile, straight or recurved after anthesis. 

 Stigma cleft into 2 lamellate lobes; style short or none; ovary 1 -celled; ovules numerous. 

 Capsule sessile or stipitate, 2-valved. Seeds numerous, winged or wingless. [Named for 

 King Gentius of Illyria.] 



A genus of about 300 species of wide distribution in the arctic and the cooler parts of the north temperate 

 zone; also in the Andes, New Zealand, Australia, and Tasmania. Type species, Gentiana lutea L. 



Calyx with an intracalycine membrane inside the tube; corolla plicate, with cleft or merely emarginate plaits in 

 the sinuses; filaments attached near the middle of the corolla-tube; ovary bearing nectariferous pits on its 

 base. (Subgenus Etigentiana) 



Plaits of the sinuses 2-cleft; leaves not white-margined; flowers usually cymose. (Section Pneumonanthe) 



Perennials; stems striate; seeds winged. 



Intracalycine membrane entire or S-Iobed. 



Membrane entire; dwarf alpine plants, 5-15 cm. high. 1. G. Newberryt. 



Membrane 5-lobed; plants taller, 20 cm. or more high. 



Flowers sessile in the axils of 2 bracts. 



Floral bracts linear-lanceolate; calyx-lobes linear, unequal, 2 often about 2 mm. long, 

 the others reduced to mucronate points. 2. G. affinis. 



Floral bracts ovate or ovate-lanceolate; calyx-lobes lanceolate or oblanceolate, 8-12 mm. 

 long, well-exceeding the tube. 3. G. oregana. 



Flowers, at least some of them, on pedicels 10-15 mm. long. 4. G. sceptrum. 

 Intracalycine membrane deeply 2-lobed. 



Corolla-lobes finely serrulate; lobes of the plaits in the sinuses produced into capillary setae. 

 Leaves ovate-lanceolate, the upper pair almost concealing the flowers; calyx-tube 12-15 mm. 

 long; lobes of the plaits with several capillary setae about equaling the corolla-lobes. 



5. G. settgera. 



Leaves oblong-lanceolate, the upper pair reduced and not concealing the flowers; lobes of the 

 plaits with 2 capillary setae about half as long as the corolla-lobes. 



6. G. bisetaea. 



Corolla-lobes with entire margins; lobes of the plaits acute or short-acuminate, but not forming 

 capillary setae. 7. G. calycosa. 



Annuals; stems smooth; flowers cymose; seeds oblong, not winged. 8. G. Douglasiana. 



Plaits in the sinuses broad and merely emarginate; leaves white-margined; flowers solitary at the ends of the 

 branches; intracalycine membrane nearly entire, only shallowly notched between the calyx-lobes; seeds 

 not winged. (Section Chondrophylla) 



Corolla greenish purple; capsule long-stipitate and exserted beyond the calyx, ellipsoid. 



9. G. Fremontii. 



Corolla azure-blue; capsule subsessile, linear-oblong, enclosed in the calyx. 



10. G. prostrata americana. 



Calyx without an intracalycine membrane; corolla without plaits in the sinuses; nectariferous pits borne well down 

 on the corolla-tube. (Subgenus Gentianella) 



Corolla-tube with a fringe of lacinae on the throat; style none; seeds not winged. (Section Amarella) 

 Flowers clustered; plants 30-40 cm. high. 11. G. Amarella. 



Flowers solitary; plants 5-10 cm. high. 12. G. tenella. 



Corolla-tube without lacinae; style 1-5 mm. long. (Section Crossopetalum) 



Plants always with a simple stem; calyx-lobes never with a black midrib; corolla campanulate; seeds 

 smooth, cylindric with an enlarged collar-like center. 13. G. simplex. 



Plants with a simple or branched stem; calyx-lobes with a black excurrent midrib; seeds oval, covered 

 with minute swollen processes. 14. G. holopetala. 



