OPUNTIA. 189 



Opuntia pittieri differs from 0. inaequilateralis in having the young joints thinner, 

 somewhat tuberculate, and with longer leaves; the areoles, too, are filled with brown or 

 purple wool, while the glochids develop more slowly or never appear. 



Figure 232 represents a joint of the type plant. 



211. Opuntia cordobensis Spegazzini, Anal. Mus. Nac. Buenos Aires III. 4: 513. 1905. 



Much branched, the trunk i to 2 meters long, 20 cm. in diameter, very spiny ; joints large, 3 dm. 

 long or more, broadly oblong to obovate ; areoles prominent, numerous ; spines i to 6, white, somewhat 

 spreading, a little flattened and twisted; flowers usually on the margins of the joints; petals about 

 12, yellow; fruit pyriform, yellowish both within and without, 8 cm. long; seeds about 3 mm. long. 



Fig. 232. — O. pittieri. X0.4. Fig. 234.— Fruit of O. cordobensis. X0.7. Fig. 233. — O. cordobensis. X0.4. 



Type locality: Near Cordoba, Argentina. 



Distribution: Northern Argentina. 



The only white-spined species observed by Dr. Rose in 19 15 about Cordoba were 

 0. ficus-indica, in cultivation, and what we have taken to be O. cordobensis. The latter 

 is very abundant, growing on the hills about the city, and sometimes planted as hedges. 

 Dr. Spegazzini states that it has the habit of 0. labouretiana. 



Figure 233 represents a joint of the plant collected by Dr. Rose near Cordoba, Argen- 

 tina, in 1915; figure 234 represents the fruit as collected by J. A. Shafer at Calilegua, 

 Argentina, in 1917 (No. 197). 



