CEPHALOCEREUS. 



6. Cephalocereus macrocephalus Weber in Schumann, Gesamtb. Kakteen 197. 1897. 



Pilocereus macrocephalus Weber, Diet. Hort. Bois 966. 1898. 

 Cereus macrocephalus Berger, Rep. Mo. Bot. Gard. 16: 62. 1905. 



Plant of great-size, 10 to 16 meters high, with a very solid woody trunk 3 to 6 dm. in diameter, 

 simple or with a few ascending branches; pseudocephalium not so conspicuous as in Cephalocereus 

 senilis; ribs numerous (about 24), low, obtuse, pale green; radial spines about 12, spreading; central 

 spines several, sometimes 6 cm. long; flowering areoles spineless but bearing white, stiff hairs or 

 weak bristles; perianth about 5 cm. long, the tube bearing a few distant scales, the limb short, the 

 outer segments rounded. 



Type locality: Tehuacan, Mexico. 



Distribution: Southern Puebla, Mexico. 



Dr. Rose found this species very common on a single hill near Tehuacan, forming a 

 forest of considerable size. The individual plants are often very large and the trunk is 

 so stout and woody that one can not cut down the plants readily, as is the case with Cepha- 

 locereus senilis and some other species of this genus. 



Illustrations: Contr. U. S. Nat. Herb. 10: pi. 43, f. B; MacDougal, Bot. N. Amer. 

 Des. pi. 15; Nat. Geogr. Mag. 21: 698; Mollers Deutsche Gart. Zeit. 29: 351. f. 6. 



Plate i is from a photograph taken by Dr. MacDougal near Tehuacan in 1906. 



7. Cephalocereus pentaedrophorus (Labouret). 



Cereus pentaedrophorus Labouret, Monogr. Cact. 365. 1853. 



Pilocereus polyedrophorus Lemaire, Rev. Hort. 1862: 428. 1862. 



Pilocereus pentaedrophorus Console in Schumann, Gesamtb. Kakteen 174. 1897. 



Stems very slender, usually only 2 to 5 meters, rarely 7 or occasionally 10 meters high, 10 cm. 

 in diameter or less, bluish, glaucous especially toward the growing tip; ribs usually 4 to 6, but 



occasionally as many as S; areoles without wool, 

 often large, separated by horizontal grooves or de- 

 pressions; spines yellow, various as to size and num- 

 ber, usually 6 to 12, the longest often 4 cm. long; 

 flowers 4 to 6 cm. long ; perianth-tube bent near the 

 middle; ovary and tube green, glabrous, rarely with 

 a few minute scales; perianth-segments small, white; 

 fruit depressed-globose, 3 cm. broad; pulp red, juicy. 



Type locality: Moro-Oueimado, Bahia, 

 Brazil. 



Distribution: Very common in the brush 

 country of Bahia, Brazil, but not found in dry 

 parts of that state. 



Labouret (Monogr. Cact. 365. 1853) gives 

 Cereus pentalophorus Labouret and Cereus pcnta- 

 gonus glaucus Morel as synonyms. 



FIG. 31. Cephalocereus pentaedrophorus. 



Pig. 32. Fruit of Cephalocereus pentaedrophorus. Xo 6. 

 Fig. 33. Flower of same. Xo.6. 



This species differs from its relatives in its smaller flowers and fruits, in the flower- 

 tube being more or less curved or sometimes abruptly bent, and in the flowering areoles 



