1238 CONTRIBUTIONS FEOM THE NATIONAL HERBARIUM. 



Flowers 8 mm. long or less. 



Calyx lobes spreading, elongate, acuminate 9. C. incanum. 



Calyx lobes erect, short, obtuse, or the calyx truncate. 

 Leaves coriaceous when mature, prominently reticulate-veined ; 



racemes chiefly straight, not nodding 10. C. berlandieri. 



Leaves thin, not prominently reticulate; racemes usually curved 

 and nodding. 

 Calyx 5 mm. long; corolla tube not or scarcely exceeding the 



calyx 11. C. bourgeauianum. 



Calyx 3 mm. long; corolla tube conspicuously exceeding the 



calyx 12. C. ovatifolium. 



Leaves glabrous beneath or very minutely and obscurely puberulent. 

 Corolla lobes finely puberulent outside. 

 Leaves very obtuse, rounded, or emarginate at apex, coriaceous, with 



very prominent reticulate venation 13. C. ellipticum. 



Leaves mostly acute or acuminate, thin or coriaceous, the venation not 

 very prominent and reticulate. 



Calyx 1.5 to 2 mm. long 14. C. glabrum. 



Calyx 3.5 to 4.5 mm. long. 

 Leaves very lustrous on the upper surface; branches subterete. 



15. C. lucidum. 



Leaves dull; branches sharply 4 or 6-angulate 16. C. hexangulare. 



Corolla lobes glabrous outside, often ciliate. 

 Petioles 5 mm. long or less. Corolla lobes strongly ciliate. 



17. C. pringlei. 

 Petioles mostly 1 to 4 cm. long. 



Corolla 6 to 7 mm. long, the lobes eciliate or nearly so 18. C. affine. 



Corolla 3.5 to 4 mm. long, the lobes strongly ciliate 19. C. schottii. 



1. Citharexylum brachyantliuni A. Gray, Syn. Fl. ed. 2. 2^: 458. 1886. 



Lycium bra chy nut hum A. Gray; Hemsl. Biol. Centr. Amer. Bot. 2: 426. 1882. 



Coahuila, Nuevo Leon, Zacatecas, and Hidalgo ; type from Coahuila. West- 

 ern Texas. 



Shrub, 1 to 1.5 meters high, with stiff subspinose branchlets; leaves linear- 

 spatulate to obovate, subsessile, entire, puberulent or pubescent ; flowers soli- 

 tary or fasciculate; calyx about 2.5 mm. long, 5-dentate; corolla white, 4 mm. 

 long ; fruit 6 mm. in diameter. 



2. Citharexylum tetramerum T. S. Brandeg. Univ. Calif. Publ. Bot. 3: 390. 



1909. 



San Luis Potosi and Puebla; tyi>e from Cerro de Matzize, near San Luis 

 Tultitlanapa, Puebla. 



Shrub, 2 to 4 meters high ; leaves oblanceolate or oblong-oblanceolate, 2.5 

 to 6 cm. long, short-petiolate, obtuse or subacute, glabrous beneath or obscure- 

 ly puberulent, glandular-punctate; flowers solitary or in 2 or 3-flowered ra- 

 ceme?, 4-parted; calyx 2.5 mm. long; corolla white, 4 to 5 mm. long. 



It is probable that the oldest name for this plant is C. lycioides D. Don.^ That 

 species was described from Mexico, no definite locality being given. 



3. Citharexylum altamiranum Greenm. Field Mus. Bot. 2: 259. 1907. 

 Queretaro ; type from Hacienda del Ciervo. 



Leaves elliptic to suborbicular, 2 to 4 cm. long, obtuse or rounded at apex, 

 usually entire, hirsute-pubescent; calyx 5-dentate; fruit 7 to 8 mm. long. 



'Edinburgh New Phil. Journ. 11: 237. 1831. 



