OPUNTIA. 



i6 7 



Plate xxxi, figure i, represents a flowering joint of a plant collected near Brownsville, 

 Texas, by Dr. Rose in 1913 ; figure 2 represents a flowering joint of a plant obtained by the 

 same collector at the same locality; plate xxxn, figure i, represents a flowering joint of a plant 

 sent by Mr. M. Mackensen from the type locality of 0. Icptocarpa in 1910; figure 2 shows 

 the fruit of the same. 



180. Opuntia cantabrigiensis Lynch, Card. Chron. III. 33: 98. 1903. 



Oputi/ia engelmamiii niija Griffiths and Hare, N. Mex. Agr. Exp. Sta. Bull. 60: 44. 

 cuija Britton and Rose, Smiths. Misc. Coll. 50:529. 1908. 



1906. 



Rounded bushy plant, i to 2 meters high; joints orbicular to obovate, 12 to 20 cm. long, rather 

 pale bluish green; areoles remote, large, filled with brown wool; spines usually 3 to 6 but sometimes 

 more, somewhat spreading, acicular, yellow with brown or reddish bases, 1.5 to 4 cm. long; glochids 

 numerous, large, i cm. long or more, yellowish, not forming a brush; flowers 5 to 6 cm. long, yel- 

 lowish with reddish centers ; upper areoles on the ovary bearing long bristles ; stigma-lobes green ; 

 fruit, globular, about 4 cm. in diameter, purple; seeds numerous, small, 4 mm. in diamter. 



Type locality: Described from specimen in Cambridge Botanic Garden, England. 



Distribution: Very common in the States of San Luis Potosi, Queretaro, and Hidalgo, 

 Mexico. 



Opuntia chrysacantha (Berger, Hort. Mortol. 231. 1912, name only), an undescribed 

 species, probably belongs here. 



Our determination of the identity of 0. cantabrigiensis and 0. cuija is based on a living 

 plant of the former received from Mr. Lynch. 



Illustrations: N. Mex. Agr. Exp. Sta. Bull. 60: pi. 2, as Opuntia ciigchnaiinii cuija; 

 Card. Chron. III. 30: f. 123, as Opuntia engelmannii. 



Figure 204 represents joints of a nlant collected by Dr. Rose near Ixmiquilpan, Hidalgo, 

 Mexico, in 1905. 



Fro. 204. O. cantabrigiensis. Xo.4. 



FIG. 205. O. procumhens. 



181. Opuntia procumbens Engelmann, Proc. Amer. Acad. 3: 292. 1856. 



Stems low and spreading, forming broad masses; joints "always edgewise," orbicular, 2 to 4 or 

 even 5 dm. in diameter, yellowish green, somewhat glaucous; areoles distant (3 to 5 cm. apart), 



