CEPHALOCEREUS. 49 



Illustration: Contr. U. S. Nat. Herb. 12: pi. 64. 



Figure 71 is from a photograph taken near Salama, Guatemala, by W. R. Maxon in 1905. 



32. Cephalocereus piauhyensis (Giirke). 



Cereus piauhyensis Gtirkc, Monatsschr. Kaktccnk. 18: 84. 1908. 



Plant tree-like, 5 to 10 meters high; trunk woody, 3 to 5 dm. in diameter, with a smooth, 

 nearly spineless bark; branches 20 to 100, slender, bluish green; ribs 13, low; areoles large, each flower- 

 ing one bearing a tuft of long white hairs; spines numerous, yellowish brown, acicular, unequal, the 

 longest 3 cm. long; flowers 3.5 to 4 cm. long, naked; fruit depressed, glaucous, 4 cm. broad, naked. 



Type locality: Rocks of the Serra Branca, Piauhy, Brazil. 



Distribution: On the dry hills in the caatinga along the Sao Francisco River in the States 

 of Bahia and Piauhy, Brazil. 



It resembles Cephalocereus catingicola, but has more slender branches, more ribs, smaller 

 flowers, and smaller fruits. The trunk is woody, very heavy, and is often sawed into 

 boards and used for making picture frames and the like. We have referred here the plant 

 collected by Dr. Rose in Bahia without having seen the type of the species. 



Figure 72 is from a photograph taken by Paul G. Russell east of Joazeiro, Bahia, 

 Brazil, in 1915. 



33. Cephalocereus lanuginosus (Linnaeus) Britton and Rose, Contr. U. S. Nat. Herb. 12: 417. 1909. 



Cactus lanuginosus Linnaeus, Sp. PI. 467. 1753. 



Cereus lanuginosus Miller, Card. Diet. ed. 8. No. 3. 1768, as to name only. 



Cereus crciiu/alus Salm-Dyck, Observ. Bot. 3: 6. 1822. 



Cereus laniigino.'iiis glaucescens Pfeiffer, Enum. Cact. 80. 1837. 



Pilocerens crcnulatus Riimpler in Forster, Handb. Cact. ed. 2. 655. 1885. 



Pilocereus lanuginosus Riimpler in Forster, Handb. Cact. ed. 2. 672. 1885. 



Often tall and tree-like, either nearly simple or much branched; branches elongated, 9 to 13- 

 ribbed, bright blue, somewhat glaucous; ribs rounded when young, separated by acute intervals; 

 spines acicular, light yellow when young ; young areoles all woolly, the flowering ones bearing dense 

 tufts of wool, but this not very long; flowering areoles confined to 2 to 4 ribs on the south side of the 

 plant; flower-buds short, green, rounded at the apex; flowers opening in the early evening, 6 cm. 

 long; outer perianth-segments short, green; inner perianth-segments ovate, white, short; stamens 

 numerous, included; style rigid, white, slightly exserted; stigma-lobes white; fruit depressed, red, 

 naked. 



Type locality: Island of Curasao. 



Distribution: Curacao, Aruba, Bonaire. 



Cereus crenulatus gracilior Salm-Dyck (Hort. Dyck. 63. 1834) is only a mentioned name. 



Illustrations: London, Encyl. PI. f. 6861, as Cactus lanuginosus; Rep. Mo. Bot. Gard. 

 16: pi. 4, f. 5, as ( 'ercns lanuginosus; Hermann, Par. Botavus pi. 1 15, as Cereus erectus, etc; 

 Monatsschr. Kakteenk. 12: 56, as Pilocereus lanuginosus. 



Figure 73 is from a photograph taken on Curasao by Mrs. J. N. Rose in 1916. 



34. Cephalocereus brooksianus Britton and Rose, Torreya 12: 14. 1912. 



Cereus brooksianus Vaupel, Monatsschr. Kakteenk. 22:66. 1912. 



Plant 3 to 6 meters high, stout, much branched at base, bluish green, glaucous; ribs 8 or 9, 

 obtuse; areoles closely set, in flowering specimens almost contiguous, bearing silky hairs when young 

 and tufts of long white hairs at flowering ones; spines about 16, acicular, up to 3 cm. long, yellow, 

 all somewhat similar, the upper ones in each areole ascending; flowers 5 to 6 cm. long, opening in the 

 evening, odorless, somewhat flattened; tube stout, rigid, green, with only 2 or 3 small scales; inner 

 perianth-segments about 10, rather rigid, broad, a little spreading; throat of flower wide; stamens 

 very numerous, all included; filaments white, attached all over the long broad throat, 3 cm. long; 

 tube proper very short, 8 mm. long or less; style white, rigid, 5 cm. long; ovary naked. 



Type locality: Near Novaliches, about six miles south of Guantanamo, Cuba. 

 Distribution: Dry, rocky situations, provinces of Oriente and Santa Clara, Cuba. 

 Plate vin, figure i, is from a plant collected by Dr. Britton at Guantanamo Bay, Cuba, 

 in 1909, which flowered at the New York Botanical Garden in 1913. 



