CEPHALOCEREUS. 



47 



Schumann (Gesamtb. Kakteen 184. 1897) by mistake attributed the name Pilocereus 

 swartzii to Grisebach. 



Figure 70 is from a photograph obtained by Wm. Harris near Port Henderson, Jamaica. 



28. Cephalocereus polygonus (Lamarck) Britton and 

 Rose, Contr. U. S. Nat. Herb. 12: 418. 1909. 



Cactus polygonus Lamarck. Encycl. i : 5,39. 1783. 

 Ccreus polygonus De Canclollc, I'roclr. 3: 466. 



1828. 

 Pilocereus plumieri Lcmaire, Rev. Hort. 1862: 



427. 1862. 

 Pilocereus scMumbcrgeri Weber in Schumann, 



Gesamtb. Kakteen 186. 1897. 

 Pilocereus polygomis Schumann, Gesamtb. Kak- 



teen 196. 1897. 



Plants at first simple, but when old with large, 

 much branched tops, 3 meters high or more; trunk 

 erect, i to 1.5 meters long below the branches; 

 branches elongated, erect or ascending, 5 to 13- 

 ribbcd ; young growth, at least in some forms, very 

 blue; ribs rather narrow, 2 cm. high or more, grooved 

 on their sides; areoles closely set, often only i cm. 

 apart, producing long tawny wool, longer than the 

 short acicular spines; old areoles without wool, vigor- 

 ous and producing very different spines from the new 

 ones; first spines acicular or setaceous, i to 1.5 cm. 

 long, yellow, becoming gray or darker by age ; sup- 

 plementary spines elongated, subulate, yellowish 

 brown, 2 to 7 cm. long; flowering areoles very 

 woolly; flowers 5 to 6 cm. long, white; perianth- 

 segments rounded or somewhat acutish; fruit glob- 

 ular, 3 to 4 cm. in diameter; seeds numerous, 

 small, 2 cm. long, smooth, shining. 



Type locality: Santo Domingo. 



Distribution: Dry parts of Hispaniola. 



Illustration: Plumier, PI. Amer. ed. Bur- 

 mann, pi. 196. 



Plate vii, figure i, is from a photograph 

 taken by Paul G. Russell near Azua, Santo 

 Domingo, in 1913. 



Cephalocereus swartzii. 



29. Cephalocereus gaumeri sp. nov. 



Plant 6 meters high, light green, slender, often 

 only 2 to 3 cm., but sometimes 6 cm., in diameter; 

 ribs 8 or 9, 6 to 8 mm. high; areoles 6 to 10, bear- 

 ing short felt and cobwebby hairs when young ; flowering areoles bearing tufts of white wool i to 2 

 cm. long, i to 2 mm. apart; spines numerous, 15 to 25, acicular, i to 5 cm. long, yellowish brown 

 when young; flowers "light green," 5 to 7 cm. long; scales on the ovary and lower part of the 

 flower-tube few, minute, acute; scales on the upper part of the tube and outer perianth-segments 

 broadly ovate, acute; inner perianth-segments oblong, acute; stamens included; style long-exserted; 

 stigma-lobes 1 2 ; fruit depressed, brownish, somewhat ridged, 4.5 cm. long. 



This species has been repeatedly collected by Dr. George F. Gaumer in Yucatan and 

 has been distributed by him under various numbers. In 1918 he sent living plants to the 

 New York Botanical Garden and these flowered the same year. This number (No. 23934) 

 is made the type of the species. 



vSchott also collected this species in Yucatan and indicated it as a new species of Cereus, 

 but this was never published. His sheet, now in the Field Museum of Natural History, 

 bears drawings and paintings of the flowers and fruit. 



