OPUNTIA. 



191 



Series 22. ROBUSTAE. 



Tall or large plants with blue or bluish green joints, the spines, when present, white or yellowish. 

 Two of the species are widely distributed in warm regions through cultivation for their edible fruits; 

 the other is known in cultivation only in central Mexico. All are presumably Mexican in origin. 



KEY TO SPECIES. 



Joints orbicular to broadly obovate or 



elliptic. 



Fruit deep red, 7 togcm. in diameter. 213. 0. robtista 

 Fruit greenish white, 4 to 5 cm. in 



diameter ...................... 214. O. guerrana 



Joints oblong, narrowed at both ends. . 215. 0. ftisiaiulis 



213. Opuntia robusta Wendland in Pfeiffer, 

 Enum. Cact. 165. 1837. 



Opuntia flavicans Lemaire, Cact. Gen. Nov 



Sp. fii. 1839. 

 Opuntia larrcyi Weber in Coulter, Contr. U. S. 



Nat. Herb." 3: 423. 1896. 

 Opuntia gorda Griffiths, Monatsschr. Kakteenk. 



23: 134- 



FIG. 237. Opuntia quimilo. 



Often erect, sometimes 5 meters high, usually 

 much branched; joints orbicular to oblong, 20 to 

 25 cm. long by to to 12.5 cm. broad, very thick, 

 bluish green, glaucous; leaves 4 mm. long, reddish, 

 acute; spines 8 to 12, stout, very diverse, brown 

 or yellowish at base, white above, up to 5 cm. long, 

 but often wanting on greenhouse specimens; 

 flowers 5 cm. broad, yellow; stigma-lobes green; 

 fruit globular to ellipsoid, at first more or less 

 tuberculate, deep red, 7 to 9 cm. long. 



Type locality: In Mexico. 



Distribution: Central Mexico; cultivated 

 in Argentina. 



This is one of the few species of Opuntia 

 of which we have not been able to verify the 

 original publication. It was redescribed by 

 Pfeiffer in 1837. 



Opuntia camuessa Weber (Diet. Hort. Bois 895. 1898) was given as a synonym of 0. 

 robusta, but was never described; and the same is true of 0. piccolominiana Parlatore 

 (Schumann, Gesamtb. Kakteen 741. 1898). 



The variety Opuntia robusta viridior Salm-Dyck (Forster, Handb. Cact. 487. 1846) 

 was never described. 



Opuntia albicans Salm-Dyck (Hort. Dyck. 361. 1834) we do not know, but A. Berger, 

 who has grown a plant under that name at La Mortola, says it is closely related to O. 

 robusta, while in the New York Botanical Garden are specimens labeled 0. albicans which 

 are difficult to distinguish from 0. ficus-indica. Here belong the following: 0. prate 

 Sabine (Pfeiffer, Enum. Cact. 155. 1837), given as a synonym of O. albicans; O. albicans 

 laevior Salm-Dyck (Cact. Hort. Dyck. 1849. 67. 1850), name only; and 0. pruinosa Salm- 

 Dyck (Cact. Hort. Dyck. 1849. 67. 1850) given as a synonym of 0. albicans laevior. 



Opuntia larreyi, a manuscript name of Weber, which was published by Coulter in 

 1896, is based on the plant known to the Mexicans as camuessa. Weber gave it the name 

 of O. camuessa, as shown above, but did not publish it; it is usually considered to be only 

 a race of 0. robusta, but Dr. Griffiths considers it a distinct species, even referring it to a 

 different series, the Ficus-indicae (N. Mex. Agr. Exp. Sta. Bull. 64: 56. 1907). 



