STANDLEY TREES AND SHRUBS OF MEXICO. 879 



36. Opuntia basilaris Engelm. & Bigel. Proc. Ainer. Acad. 3: 298. 1856. 

 Northern Sonora. Southwestern United States. 



Stems low, growing in clumps, either prostrate or erect, sometimes 1.2 meters 

 higli ; joints broadly obovate, 8 to 20 cm. long, slightly pubescent or glabrous, 

 usually highly colored; areoles numerous, filled with white to brown wool 

 and brownish glochids ; spines none or rarely a few at upper areoles; flowers 



6 to 8 cm. long, deep purple or sometimes white ; fruit dry, globular to obovoid ; 

 seeds thick, 6 to 10 mm. broad. 



The young fruit was eaten by the Coahuilla Indians of California after 

 having been cooked for about 12 hours in a pit lined with hot stones. The 

 Panamint Indians gathered the young joints in May and June, brushed off 

 the spines with bunches of grass, and dried them in the sun. The dried joints 

 were later boiled with salt and eaten. The tender joints were also cooked in 

 pits lined with stones, and were eaten immediately or dried and stored for use 

 in winter. 



37. Opuntia microdasys (Lehm.) Pfeiff. Enum. Cact. 154. 1837. 

 Cactus microdasi/s Lehm. Ind. Sem. Hamb. 16. 1827. 

 Opuntia pulvi^iata DC. Mem. Mus. Hist. Nat. 17: 119. 1828. 

 Northern Mexico. 



Often low and creeping but sometimes nearly erect and 40 to 60 cm. high; 

 joints oblong to orbicular, 10 to 15 cm. long, soft-velvety, usually pale green, 

 spineless ; areoles conspicuous, closely set, filled with numerous yellow or 

 brown glochids; flowers usually produced in abundance, 4 to 5 cm. long, pure 

 yellow, or tinged with red; petals broad, retuse; fruit dark red, juicy, nearly 

 globular; seeds 2 to 3 mm. broad. "Cegador" (Zacatecas) ; "nopal cegador" 

 (Durango) ; "nopalillo cegador" (Nuevo Leon). 



The name "cegador" ("blinding") is given because of the fact that the very 

 numerous glochids get into the eyes of pasturing animals and sometimes cause 

 blindness. 



38. Opuntia macrocalyx Griffiths, Rep. Mo. Bot. Gard. 19: 268. 1908. 

 Described from cultivated plants ; perhaps in Coahuila. 



Plants ascending or erect, about 1 meter high ; joints long-obovate, com- 

 monly about 22 cm. long, gray-green, pubescent ; areoles 2 to 3 mm. in diameter, 

 1 cm. apart ; wool tawny ; glochids reddish brown, 1 mm. long ; spines none ; 

 flowers yellow; fruit red, the pulp greenish, long-obovoid to cylindric, about 



7 cm. long; seeds few, 3 mm. in diameter. 



39. Opuntia rufida Engelm. Proc. Amer. Acad. 3: 298. 1856. 

 Northern Mexico. Texas. 



More or less erect, 20 to 150 cm. high, with a somewhat definite trunk; 

 joints nearly orbicular, 6 to 25 cm. in diameter, thickish, velvety-tomentose, 

 dull grayish green ; areoles large, filled with numerous brown glochids ; 

 flowers yellow to orange, 4 to 5 cm. long (including the ovary) ; petals 

 obovate, 2 to 2.5 cm. long; ovary globular, 1.5 cm. in diameter, umbilicate, 

 with large areoles; fruit bright red. "Nopal cegador" (Ochoterena). 



40. Opuntia pycnantha Engelm.; Coulter, Contr. U, S. Nat. Herb. 3: 423. 189G. 

 Baja California ; type from Magdalena Bay. 



Often low and creeping but sometimes forming a clump 20 cm. high ; 

 joints oblong to orbicular, often 20 cm. long, puberulent or papillose, usually 

 nearly hidden by the thick mass of spines ; areoles large and closely set, 

 the upper part filled with yellow or brown glochids and the lower part with 



8 to 12 yellow or brown, reflexed spines 2 to 3 cm. long; fruit 4 cm. long, 

 very spiny ; seeds 2 cm. broad, very thick. 



