Usually in moist soil along streams, in marshes with willows and in seepage 

 areas, prairies and meadows, and on hillsides in cen. and w. Tex., N.M. (De 

 Baca, Grant, San Juan and Dona Ana cos.) and Ariz, (throughout state), Mar.- 

 Nov.; from Tex. to Mo., w. to Ut., Nev., N.M., Ariz, and n. Mex. 



The var. breviflorum Shinners of central and south Texas is distinguished from 

 var. calycosum by its smaller corolla lobes (5-7 mm. long) and the calyx lobes 

 (6-10 mm. long) being shorter than the corolla tube. It occurs in similar habitats 

 but is also found in salt marshes along the coast. 



2. Centaurium Beyrichii (T. & G.) Robins, var. Beyrichii. Mountain pink. 



Plant slender, to 3 dm. tall, at length fastigiately branched; cauline leaves 

 linear to very narrowly linear-oblanceolate, to 3 cm. long and 3 mm. wide, the 

 uppermost nearly filiform; pedicels about equal to or shorter than the calyx; 

 flowers numerous, pink; corolla tube equal to or somewhat exceeding in length 

 the elliptic to linear-oblong lobes (7-12 mm. long), about half again the length 

 of the calyx lobes; seeds dark-brown. Erythraea Beyrichii T. & G. 



On rocky open limestone slopes and in seepage on granite boulders from n.-cen. 

 to w. Tex., where it is rare, and Okla. {Waterfall), May-Aug.; also Ark. 



The var. glanduliferum Correll, of west Texas, is a small much-branched plant 

 about 15 cm. tall. It is distinguished from var. Beyrichii by the occurrence of 

 numerous minute glands, especially on the leaves. It also has blackish or very 

 dark-brown seeds. 



3. Centaurium nudicaule (Engelm.) Robins. 



Rather lax glabrous biennial; stems usually with less than 6 pairs of leaves, 

 to about 3 dm. tall; the branches, pedicels and often the leaves ascending-spread- 

 ing; basal leaves forming a rosette, obovatish, 8-16 mm. long, noticeably wider 

 than the cauline leaves that are linear to linear-lanceolate; flowers few on long 

 pedicels; corolla lobes pinkish, 4 or 5, oblong, obtuse, at most 6 mm. long, nearly 

 as long as the tube; anthers linear-oblong, slightly twisted. 



Along streams, marsh areas and wet sand-gravel bars in stream beds, in Ariz. 

 (Pima and Mohave cos.), Apr.-Aug.; also Baja Calif. 



4. Centaurium exaltatum (Griseb.) Wight ex Piper. 



Plant glabrous; stems simple or usually branched, to about 3 dm. tall; leaves 

 ascending, oblong-elliptic to elliptic-lanceolate or oblanceolate, 1-3 cm. long, 

 obtuse to acute; flowers usually few, rarely solitary or many; pedicels strictly 

 erect, 1-5 cm. long, much-exceeding the subtending bract; calyx lobes 8-10 

 mm. long, subulate; corolla tube exceeding the calyx; corolla lobes pale-pink to 

 white, oblong, obtuse, 3-4 mm. long, usually about one-third as long as tube; 

 anthers oblong, about 1 mm. long, slightly twisted; stigma lobes flabellate; capsule 

 nearly twice the length of the calyx; seeds suborbicular, about 0.25 mm. long. 



In marshes with willows and tamarix, and wet places generally, often alkaline, 

 in N.M. (San Juan Co.), June-Aug.; Neb. to Wash., s. to N.M. and Calif. 



3. Eustoma Salisb. Catchfly-gentian 



Annual or short-lived perennial, more or less glaucous, with erect or ascending 

 leafy stems from a taproot and usually a rosette; leaves opposite, sessile and 

 clasping the stem, entire; flowers long-pedicelled, showy, solitary or paniculate; 

 calyx deeply cleft, the lobes long-attenuate, keeled; corolla deeply campanulate; 

 corolla lobes erect, convolute in bud, the apex entire or somewhat erose and some- 

 times apiculate; stamens 5 or 6, inserted on the corolla throat; anthers oblong, 

 versatile, straight or recurved; style slender, subpersistent, with a prominently 

 two-lipped stigma; capsule ellipsoid, 2-valved, many-seeded. 



An American genus of several species, mostly in Mexico. 



1318 



