530 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 5a 



OPUNTIA RUBRIFOLIA Engelm. 



Opuntia rubrifolia Engelm.; Coult. Contr. Nat. Herb. 3: 424. 1896. 



Type locality : St. George, Utah. 



Distribution : Only known from the type locality. 



OPUNTIA PROCUMBENS Engelm. 



Opuntia procumbens Engelm. Proc. Am. Acad. 3:292. 1856. 



Type locality : San Francisco Mountains to Cactus Pass, Arizona. 



Distribution : Texas to Arizona. 



Illustration: Pac. R. Rep. 4: pi. 6. figs. 4, 5. 



Series FULVISPINOSAE 



Bushy or spreading brown-spined plants, the spines sometimes 

 brown only toward the base; fruits fleshy. 



OPUNTIA MEGARRHIZA Rose 



Opuntia megarrhiza Rose, Contr. Nat. Herb. 10: 126. 1906. 



Type locality : Alvarez, Mexico. 

 Distribution : San Luis Potosi, Mexico. 



OPUNTIA NIGRICANS Haw. 



Cactus nigricans Haw. Misc. Nat. 187. 1803. 

 Opuntia nigricans Haw. Syn. PI. Succ. 189. 1812. 

 Cactus tuna nigricans Sims, Bot. Mag. 38: pi. 1557. 1813. 



Type locality: Unknown. 

 Distribution : Mexico. 

 Illustration: Bot. Mag. loc. cit. 



OPUNTIA MACROCENTRA Engelm. 



Opuntia macrocentra Engelm. Proc. Am. Acad. 3:292. 1856. 



Type locality : Sand hills on the Rio Grande near El Paso. 

 Distribution : Texas to Arizona and Chihuahua. 

 Illustration : Cact. Mex. Bound, pi. 75. fig. 8. 



OPUNTIA PHAEACANTHA Engelm. 



Opuntia phacacantha Engelm. in Gray, PI. Fend. 2: 352. 1849. 

 Opuntia phaeacantha nigricans Engelm. Proc. Am. Acad. 3:293. 1856. 

 Opuntia phaeacantha brunnca Engelm. loc. cit. 1856. 



Type locality : About Santa Fe and on the Rio Grande. 

 Distribution : Texas to Arizona and Chihuahua. 

 Illustration : Cact. Mex. Bound, pi. 75. figs. 9-15. 



