STANDLEY TREES AND SHEUBS OF MEXICO. 719 



Leaves rounded or very obtuse at apex, rarely acute, the fruit then more 

 than 1 cm. in diameter. 

 Leaves 4 to 10 mm. wide, pilose beneath or in age glabrate; fruit about 



8 mm. in diameter 4. C. texensis. 



Leaves 1.5 to 7 cm. wide, tomentose beneath ; fruit over 1 cm. in diameter. 



5. C. macrocarpa. 

 Leaves acute or acuminate ; fruit 8 mm. or less in diameter. 

 Leaves glabrous on the upper surface, in age glabrate beneath. 



6. C. celtidifolia. 



Leaves pubescent on the upper surface, densely tomentose or loosely 



sericeous beneath 7. C. greggii. 



1. Colubrina glabra S. Wats. Proc. Amer. Acad. 24: 44. 1889. 

 Baja California and Sonora ; type from Guaymas, Sonora. 



Densely branched shrub, 1.5 to 3.5 meters high ; leaves mostly fasciculate, 

 orbicular to oblong-ovate, obovate, or elliptic, rounded or retuse at apex, 

 glabrous or pubescent ; flowers yellowish green ; fruit 4 to 6 mm. broad. 



2. Colubrina ehrenbergii Schlecht. Linnaea 15: 469. 1841. 



Jalisco, San Luis PotosI, and Veracruz ; type collected between Ajuntas and 

 Las Verdosas. 



Shrub or small tree ; leaves short-petiolate, oblong-ovate to broadly ovate, 



4 to 8 cm. long, acutish, coriaceous, glabrous or nearly so on the upper surface ; 

 fruit 5 to 6 mm. in diameter. 



3. Colubrina glomerata (Benth.) Hemsl. Biol. Centr. Amer. Bot. 1: 200. 1880. 

 Rhammis glomerata Benth. PI. Hartw. 9. 1839. 



'iZizyphus acuminata Benth. Bot. Voy Sulph. 78. 1844. 

 Barcena guanajuatensis Duges, Rev. Cienc. Mex. 1 : 8. 1879. 

 Colubrina arhorea T. S. Brandeg. Zoe 4: 401. 1894. 

 Coluirina mexicana Rose, Contr. U. S. Nat. Herb. 3: 315. 1895. 

 Baja California to Chihuahua, Guanajuato, Puebla, and Oaxaca ; type from 

 Zacatecas. 



Shrub or small tree, 2 to 6 meters high ; leaves lanceolate to broadly ovate, 



5 to 12 cm. long, acute to long-acuminate, obtuse or rounded at base, bright 

 green ; fruit 6 to 8 mm. in diameter. 



The species is somewhat variable in leaf form, but the leaves vary about 

 as much upon a single plant as in the whole series of specimens. 



4. Colubrina texensis (Torr. & Gray) A. Gray, Bost. Journ. Nat. Hist. 6: 169. 



1850. 

 Rhamnus texensis Torr. & Gray, Fl. N. Amer. 1: 263, 1838. 

 Coahuila and Nuevo Leon. Texas. 



Shrub, 1 to 2 meters high, densely branched ; leaves short-petiolate, elliptic 

 or obovate, acute to rounded at base. 



5. Colubrina macrocarpa (Cav.) Don, Hist. Dichl. PI. 2: 36. 1832. 

 Ceanothus macrocarpus Cav. Icon. PI. 3: 38. pi. 276. 1794. 

 Colubrina megacarpa Rose, Contr. U. S. Nat. Herb. 8: 50. pi. 11. 1903. 

 Colubrina lanulosa Blake, Contr. Gray Herb. 52:74. 1917. 

 Michoacfin, Guerrei'o, Queretaro, and Puebla. 



Shrub or small tree, 2.5 to 4 meters high ; leaves elliptic-oblong to 

 rounded-ovate, 3 to 8 cm. long, rounded or rarely acutish at apex, rounded 

 or cordate at base, densely pubescent on the upper surface. " Caf6 cimarr6n " 

 (Queretaro). 



