FEROCACTUS. 



139 



Echinocactus pfersdorffii Hortus may be referable here. It is probable that E. pfers- 

 dorffii Hildmann Catalogue (Monatssehr. Kakteenk. 5: 92. 1905) is the same, but neither 

 was accompanied by a description. 



In cultivation this plant is simple, depressed-globose, 4.5 dm. in diameter, but in the 

 wild state sometimes cylindric and up to 6 dm. high, and described as proliferous, ribs 20, 

 perhaps even more, acute; areoles rather large, distant; radial spines usually 8, subulate, 

 somewhat curved, 4.5 cm. long; central spines usually solitary, but as many as 4 reported, 

 all yellow. 



We have followed Schumann in refer- 

 ring here various synonyms, but the indi- 

 cations are that we have more than one 

 species. Dr. Rose obtained flowers of this 

 species at La Mortola in 191 2 and his notes 

 were used in drawing up the description. 



Here belongs Cactus multangularis 

 Mocifto and Sesse (Mem. Mus. Hist. Nat. 

 Paris 17: 38. 1828), but never described 

 by them. Echinocactus electt -acanthus 

 rujispinus (Monatssehr. Kakteenk. 3: 70. 

 1893) we would also refer here. 



Echinocactus hystrichacanthus Lemaire 

 (Cact. Gen. Nov. Sp. 17. 1839) may be of 

 this relationship. This species as well as 

 E. pyenoxyphus Lemaire (Cact. Gen. Nov. 

 Sp. 16. 1839) Weber considered as only 

 varieties of E. hystrix. 



Illustrations: DeCandolle, Mem. Mus. 

 Hist. Nat. Paris 17: pi. 10, as Echinocactus 

 mclocactiformis; Monatssehr. Kakteenk. 3: 



_ , ,-. , , Fig. 146. Ferocactus melocaetnormis. 



158. f. 2; 21: 171; Schumann, Gesamtb. 



Kakteenf. 58, as Echinocactus clcctracanthus; Bliihende Kakteen 1: pi. 22, as Echinocactus 



ingens. 



Figure 146 is copied from the first illustration above cited. 



22. Ferocactus macrodiscus (Martius). 



Echinocactus macrodiscus Martius, Nov. Act. Nat. Cur. 16; 341. 1832. 

 Echinocactus macrodiscus laevior Monville in Labouret, Monogr. Cact. 197. 1853. 

 Echinocactus macrodiscus decolor Monville in Labouret, Monogr. Cact. 197. 1853. 

 Echinocactus macrodiscus multiflorus R. Meyer, Monatssehr. Kakteenk. 24: 150. 1914. 



Simple, depressed-globose or sometimes short-cylindric, sometimes 4.5 dm. in diameter; ribs 16, 

 perhaps more in some specimens, somewhat flattened, sometimes acute on the margin, somewhat 

 depressed at the distant areoles ; spines all yellow, more or less curved backward; radial spines 6 to 8, 

 mostly 2 to 3 cm. long; central spines 4, stouter and flatter than the radials, 3.5 em. long; flowers 

 5 cm. long, dark red to purple, obeonic; inner perianth-segments linear-oblong, acute; stamens and 

 style included. 



Type locality: Not definitely cited but probably on the Cumbre at about 10,000 feet, 

 in a place called El Renosco, Mexico. 



Distribution: San Luis Potosi and southward. 



We do not know this species definitely although it is supposed to have a rather wide 

 distribution in Mexico. The only specimen which we can refer with any confidence is 

 one obtained through Professor Conzatti in 1910 from Oaxaca, Mexico. 



