1. Corolla lobes 25 mm. long or less, less than 15 mm. wide 1. E. exahatum. 



1. Corolla lobes usually more than 30 mm. long, mostly 20 mm. or more wide 

 2. E. grandiflorum. 



1. Eustoma exaltatum (L.) G. Don. Fig. 627. 



Plants to 7 dm. tall, with one or several stems branched above; basal leaves 

 obovate, the cauline leaves oblong to oblong-elliptic and obtuse to subacute, to 

 9 cm. long and 3 cm. wide; pedicels to 1 dm. long; calyx lobes to 18 mm. long; 

 corolla blue to deep-lavender or white, the tube about 1 cm. long; corolla lobes 

 oblong-obovate, about twice as long as the tube or rarely to 25 mm. long; style 

 slender, about 5 mm. long; stigma lobes about 2 mm. long; capsule to 2 cm. long. 

 E. sileni folium Salisb. 



In damp places in prairies and fields, along streams or in wet meadows, often 

 in alkaline or saline soils in s. and w. Tex., N. M., (Guadalupe, Socorro, Dona 

 Ana. Otero and Chaves cos.) and Ariz. (Mohave, Yavapai, Graham, Gila, Mari- 

 copa and Pima cos.), June-Oct.; in s. U.S., Mex., Br. Hond. and W.I. 



The white-flowered plant has been designated f. albiflorum Benke. 



2. Eustoma grandiflorum (Raf.) Shinners. Lira de san pedro, bluebells. Fig. 



627. 



Plants very similar to E. exaltatum, to 7 dm. tall; leaves ovate to elliptic-oblong 

 or elliptic-lanceolate, noticeably 3-veined, to 8 cm. long and 3 cm. wide; pedicels 

 to 6 cm. long; calyx to 3 cm. long, the lobes subulate; corolla variously colored 

 blue-purple, pinkish, white or white and purple-tinged or yellowish; corolla lobes 

 3-4 cm. long, elliptic-obovate. at least 3 times as long as the tube; capsule to 2 cm. 

 long. E. Russellianum (Hook.) Sweet. 



In moist places in prairies and fields and about tanks in most of Tex. and Okla. 

 {Waterfall) , June-Sept.; Okla. and Tex., w. to Neb. and Colo., s. to Mex. 



Several forms have been segregated based on the following flower-colors; white, 

 f. Flsheri (Standi.) Shinners; white with purple-tinged lobes, f. hicolor (Standi.) 

 Shinners; pink, f. roseum (Standi.) Shinners; yellow, f. fiaviflorum (Cockll.) 

 Shinners. 



4. Gentiana L. Gentian 



Annual, biennial or perennial herbs from fleshy roots or slender rhizomes, mostly 

 glabrous; leaves opposite, petiolate to sessile and sometimes clasping; flowers soli- 

 tary to numerous in flat-topped to much-elongated cymose clusters, 4- to 5- or 

 rarely 6-merous (except the pistil), white or yellowish to bluish or purplish, often 

 with much green mottling; calyx tubular by fusion of lobes or divided to near the 

 base, sometimes lined with an inner membrane that projects above the base of the 

 often unequal lobes; corolla narrowly funnelform to salverform but usually closing 

 quickly, persistent, lobed for one-fifth to one-third its length, often either plicate 

 in the sinuses (with the plaits notched, rounded to acute or lobed or toothed) or 

 with setaceous scales at the base of the lobes on the inner surface; stamens adnate 

 to the corolla tube for one-third to three-fifths of its length, the adnate portion often 

 with free winglike margins, the free filaments often conspicuously flattened; anthers 

 versatile, erect to recurved; ovary stipitate to sessile; style usually short and rather 

 stout, ending in 2 stigmatose lobes or with enlarged crenate-margined stigmas; 

 capsules 1 -celled, 2-valved, many-seeded. 



Probably as many as 300 or more species, cosmopolitan except in Africa, mainly 

 in alpine areas. Many have beautiful, ornamental flowers. 



1. Corolla without plaits or lobes in the sinuses; calyx without an intercalycine 

 membrane inside the tube, its lobes imbricate; nectariferous pits 

 borne well down on the corolla tube (2) 



1321 



