GREEiVMAN. — GENUS HOUSTONIA. 291 



at the throat, almost fuunelform : capsule about two thirds inferior, 

 globose or short-oblong, obtuse or slightly retuse, pubescent, much ex- 

 ceeded by the erect persistent calyx-divisions ; seeds more or less crateri- 

 form, somewhat roughened on the back. — Proc. Am. Acad. xvii. 203, 

 & Syn. Fl. N. A. i. pt. 2, 27 ; llemsl. BioL Centr.-Am. Bot. iv. 47. 

 Hedyotis {Ereicotis) acerosa, Gray, PI. Wright, i. 81. Oldenlandia 

 {Ereicotis) acerosa, Gray, PI. Wiight. ii. 67, Mallostoma acerosa, 

 Hemsl. Biol. Centr.-Am. Bot. ii. 31. — Northern Mexico, Parry, nos. 7, 

 302, Gregg, no. 72, Palmer, nos. 400, 401, 402, 403 ; adjacent Texas, 

 Wright, nos. 237 (type), 1118, Thurber, no. 91, and Bigelow. 



H. polypremoides, Gray. Low, cespitose, 6 to 15 cm. high, much 

 branched from a woody perennial base: stems strict, ascending or erect, 

 usually branched above, glabrous or densely hirtellous-puberulent : leaves 

 less fascicled than in the preceding species, acerose-linear, 5 to 10 mm. 

 long, glabrous or hirtellous, margin revolute, often ciliate, midrib thick- 

 ened : flowers dimorphous, sessile or distinctly pedicellate, terminating 

 the stems and branches ; pedicels elongated in fruit, reaching a length of 

 13 mm. : calyx-divisions awl-shaped, 3 to 4 mm. long : corolla salver- 

 form or slightly funnelform, " white changing to purple," 8 to 10 mm. 

 long : capsule globose, about two thirds inferior ; seeds open-crateriform, 

 obloncr-rotuud with a short hilar ridge. — Proc. Am. Acad. xxi. 379. — ■ 

 Chihuahua, Santa Eulalia Mountains, Pringle, nos. 16,356; on route 

 from Leavenworth to El Paso, F. R. DifFenderfFer ; at junction of Dela- 

 ware Creek and Pecos River, Texas, Pope. 



Var. Bigelovii. A form with the calyx-lobes H to 2 mm. long, 

 otherwise as in the type. — Florence Mountains, Bigelow, in the Mexican 

 Boundary Survey, June, 1852, no. 437. 



* * Distinctly shrubby, 2J dm. or more high, much branched : leaves thickish, 

 more or less fascicled : inflorescence in cymes terminating the stems and 

 branches. 



■^ Leaves 3 to 10 mm. in length, much fascicled : corolla 3 to 4 mm. long. 

 H. fasciCTllata, Gray. A low bushy shrub, much branched: stem 

 and branches covered with a grayish bark : branchlets tetragonal, hirtel- 

 lous-puberulent : leaves linear, subterete, thick, rigid, nearly equalling the 

 internodes, decidedly fascicled in the axils, glabrous or hirtellous, margin 

 revolute ; stipules short, scarious, 1 to 3 setiferous-dentate : cymes few- 

 flowered : flowers small, " white, drying purple," dimorphous : calyx- 

 divisions short, about 1 mm. long, obtuse, usually puberulent : corolla 

 deeply 5-lobed ; lobes recurved ; tube long-pilose-pubescent on the inner 

 surface : capsule oblong ; seeds oblong, peltate, concavo-convex, minutely 



