WOOTON AND STANDLEY FLORA OF NEW MEXICO. 607 



4. HOUSTONIA L. Bluets. 



Annual or perennial herbs, sometimes woody at the base or throughout, 30 em. high 

 or less; leaves opposite, entire, often eiliate, mostly narrow; flowers perfect, often 

 dimorphous, solitary or oymose; hypanthium subglobose or obovoid; sepals 4; corolla 

 white or blue or bright rose pink, narrowly funnelform or salverform; stamens 4; 

 ovary 2-celled, the styles united to the narrow stigmas; capsules partly inferior, more 

 or less distinctly 2-lobed; seeds few or several in each cell. 



KEY TO THE SPECIES. 



Annual 1. H. humifusa. 



Perennials. 



Leaves fasciculate ; stems woody throughout 2. H. fasciculata. 



Leaves opposite; plants woody only near the base, if at all. 



Corolla tube 2 cm. long; plants 6 cm. high or less 5. H. rubra. 



Corolla tube less than 1 cm. long; plants more than 6 cm. 

 high. 



Pedicels reflexed after anthesis 6. H. vrightii. 



Pedicels erect. 



Stems glabrous, herbaceous; leaves soft, not 



acerose- tipped A. II. rigidiuscula. 



Stems puberulent, woody below, leaves rigid, 



acerose-tipped 3. IT. polypremoidt s. 



1. Houstonia humifusa A. Gray, Proc. Amer. Acad. 4: 314. 1859. 

 Hedyotis humifusa A. Gray, Bost. Journ. Nat. Hist. 6: 216. 1850. 



Type locality: "Open gravelly banks of streamlets, near Fredericksburg," Texas. 



Range: Western Texas to eastern New Mexico. 



New Mexico: Twenty miles south of Roswell (Earle 278). 



2. Houstonia fasciculata A. Gray, Proc. Amer. Acad. 17: 203. 1882. 

 Type locality: "Southwestern borders of Texas, at Presidio." 

 Range: Western Texas and southern New Mexico; also in Mexico. 

 New Mexico: Organ Mountains (Vasey). Upper Sonoran Zone. 



3. Houstonia polypremoides A. Gray, Proc. Amer. Acad. 21: 379. 1886. 

 Type locality : Santa Eulalia Mountains, near Chihuahua, Mexico. 

 Range: Southern New Mexico and western Texas to Mexico. 



New Mexico: Clayton; BishopsCap; White Mountains; Queen; Gray; Buchanan; 

 Lake wood; Torrance. Lower and Cpper Sonoran zones. 



4. Houstonia rigidiuscula (A. Gray) Woot. & Standi. Contr. U. S. Nat. Herb. 16: 



L75. L913. 

 Houstonia angustifolia rigidiuscula A. Gray, Syn. Fl. 2': 27. 1878. 

 Type locality: Tea 



Ram. i W etc th Texas and southern New Mexico t<> Mexico. 

 New Mexico: Tucumcari; Lincoln; Queen; Jam.' Canyon. Upper Son. mm 

 Zone. 



5. Houstonia rubra < a v. [con. PL 5: 48. pi. ■)'.',. L799. 

 Hedyotis rubra A. day, Mem. Amer. Acad. a. ser. 4: 61. 1849. 

 Oldenlandia rubra A. Gray, PI. Wright. 2: <;s. is.j:5. 



Type i <>t \i rn : "Habitat prope oppidum mexicanum [xmiquilpan." 



Range: New Mexico and Arizona (>» Mexico. 



New Mexico: Puertecito; Zuni; Albuquerque; Santa Fe; Port Wingate; Socorro 

 Mountain; Apache Teju; Round Mountain; Kast View; Buchanan. Dry hills and 

 plains, in the Upper Sonoran Zone. 



