76 THE CACTACEAE. 



9. Pachycereus lepidanthus (Eichlam). 



Cereus lepidanthus Eichlam, Monatsschr. Kakteenk. 19: 177. 1909. 



Stems simple or with few stout branches, light green; ribs 7 to 9, rather low, separated by 

 broad, rounded intervals; areoles about 1 cm. apart, small; radial spines about 10, slender, 1.5 cm. , 

 long or the longer ones 4 cm. long; the central ones stouter and somewhat flattened, 3 to 6 cm. 

 long; flowers 7 cm. long, 2.5. cm. broad ; perianth-segments arranged in 3 or 4 series, 2.5 cm. long, 8 mm. 

 broad, below red, above sepia-brown, persisting on the fruit; ovary and flower-tube covered with 

 membranous scales; fruit dry. 



Type locality: Rancho San Agustin, Guatemala. 



Distribution: Guatemala. 



This plant resembles Escontria chiotilla, with which we at one time thought it was re- 

 lated, but it has very different areoles on the stems, while the areoles in the axils of the 

 fruit scales, instead of being naked, are described as bearing felt and bristles, and the fruit 

 as dry instead of juicy. We have studied living specimens of the plant both in the New 

 York Botanical Garden and in the Cactus House at Washington, but none of these has 

 flowered, and we know its flowers and fruits only from Bichlam's description above cited. 



Illustration: Monatsschr. Kakteenk. 23: 53, as Cereus lepidanthus. 



10. Pachycereus columna-trajani (Karwinsky) Britton and Rose, Contr. U. S. Nat. Herb. 12: 

 421. 1909. 



Cereus columna-trajani Karwinsky in Pfeiffer, Enum. Cact. 76. 1837. 



Cephalophonts columna-trajani Lemaire, Cact. Aliq. Nov. xii. 1838. 



Pilocereus colitmna Lemaire, Cact. Gen. Nov. Sp. 9. 1839. 



Pilocereus later ibarbatus Pfeiffer in Forster, Handb. Cact. ed. 2. 672. 1885. 



Cephalocereus columna Schumann in Engler and Prantl, Pflanzenfam. 3 6a : 182. 1894. 



Pilocereus columna-trajani Schumann, Gesamtb. Kakteen 198. 1897, as synonym. 



Plants erect, stout, up to 15 meters high, 4.5 to 5 dm. in diameter, often simple; ribs many, 

 green; areoles oblong, bearing brown felt; radial spines 8 to 10, 12 to 25 mm. long; central spines 

 more elongated, sometimes 16 cm. long, deflexed; spines all rigid, white or horn-colored except the 

 brown bases and tips, sometimes said to be soft and erect; flowers described as purple. 



Type locality: San Sebastian, Puebla, Mexico. 



Distribution: Puebla and Oaxaca, Mexico. 



In 1906, Dr. Rose collected in the Tomellin Canyon in southern Mexico, not far 

 from the type locality of this species, what appeared to him to be this species. It 

 forms forests which cover the surrounding hills, but, unfortunately, no flowers or fruit 

 could be procured. 



Melocactus columna-trajani (Pfeiffer, Enum. Cact. 46. 1837) is usually referred to this 

 species, but is not formally published at the place here cited. 



Cereus lateribarbatus (Rev. Hort. 1862: 427. 1862) belongs here, according to Lemaire. 



Illustrations: Blanc, Cacti 77. f. 1715; Rev. Hort. 62: 129. f. 40, as Pilocereus 

 columna-trajani; Mollers Deutsche Gart. Zeit. 29: 354. f. 9; MacDougal, Bot. N. Amer. 

 Des. pi. 22, as Pilocereus tetetzo; Schelle, Handb. Kakteenk. f. 43, as Cephalocereus 

 columna-trajani. 



Plate xii is from a photograph taken by Dr. MacDougal at Tomellin Canyon, Mexico. 



Cereus tetazo Coulter (Contr. U. S. Nat. Herb. 3: 409. 1896; Pilocereus tetetzo Weber in 

 Schumann, Gesamtb. Kakteen 175. 1897), which we first confused with Pachycereus 

 columna-trajani, is not of this genus, for its ovary is glabrous and the fruit more or less 

 fleshy and edible. Coulter, however, does state that it is closely related, if not identical, 

 with one of the species of this genus, that is, Pachycereus pecten-aboriginum . It should be 

 compared with Cephalocereus macrocephalus. 



