ACANTHOCEREUS. 



123 



plant comes from near the type locality of ( 'actus pitajaya Jacquin, but we refer that species 

 to A. pentagonus, also found in northern Colombia. 



The species is near A. horridus, but has a much longer flower-tube. 



3. Acanthocereus pentagonus (Linnaeus) Britton and Rose, Contr. U. S. Nat. Herb. 12: 432. 1909. 



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



Cactus pitajaya Jacquin, Enum. PI. Carib. 23. 1761. 



Cereus pentagonus Haworth, Syn. PI. Succ. 180. 1812. 



Cactus prismaticus Willdenow, Enum. PI. Suppl. 32. 1813. 



Cereus prismaticus Haworth, Suppl. PI. Succ. 77. 1819. 



Cereus pitajaya De Candolle, Prodr. 3: 466. 1828. 

 ?Cereus undulosus De Candolle, Prodr. 3: 467. 1828. 

 ?Cactus undulosus Kosteletzky, Allg. Med. Pharm. Fl. 4: 1393. 1835. 



Cereus cognatus Pfeiffer, Enum. Cact. 106. 1837, as synonym. 



Cereus acutangulus Otto in Pfeiffer, Enum. Cact. 107. 1837. 



Cereus princeps Pfeiffer, Enum. Cact. 108. 1837. 



Cereus ramosus Karwinsky in Pfeiffer, Enum. Cact. 108. 1837. 



Cereus baxaniensis Karwinsky in Pfeiffer, Enum. Cact. 109. 1837. 



Cereus variabilis Engelmann, Bost. Journ. Nat. Hist. 5: 205. 1845. Not Pfeiffer, 1837. 



Cereus nitidus Salm-Dyck, Cact. Hort. Dyck. 1849. 211. 1850. 



Cereus vasmeri Young, Fl. Texas 276. 1873. 



Cereus dussii Schumann, Gesamtb. Kakteen 89. 1897. 



Cereus sirid Weber in Gosselin, Bull. Mus. Hist. Nat. Paris 10: 384. 1904. 



Stem clambering, usually 2 to 3, sometimes 7 meters high, but when growing in the open 

 more or less arched and rooting at the tips, then making other arches and thus forming large colonies; 

 old trunk becoming nearly round, 5 cm. in diameter or more, covered with a thick mucilaginous, 

 spineless cortex and a hard-wood axis with only a small pithy cavity; joints 3 to 8 cm. broad, 3 to 

 5-angled, low-crenate; juvenile growth nearly terete, with 6 to 8 low ribs, approximate areoles and 

 numerous short acicular spines ; areoles on normal branches 3 to 5 cm. apart ; spines gray, acicular to 

 subulate, various; radials at first 6 or 7, 1 to 4 cm. long; central spine often solitary, longer than 

 the radials; spines of old areoles often as many as 12, of which several are centrals; flowers 14 to 20 

 cm. long; tube and ovary bearing conspicuous areoles with brown felt and several subulate spines; 

 outer perianth-segments green ; inner perianth-segments white, acuminate ; fruit oblong, red, edible ; 

 cotyledons broadly ovate, 5 to 8 mm. long, thick, united at base, 

 gradually passing below into the spindle-shaped hypocotyl. 



Type locality: America, but no definite locality cited. 



Distribution: Keys of southern Florida; coast of 



Texas, south along the eastern coast of Mexico to Gua- 



Acanthocereus pentagonu 



183 



temala and Panama; the coasts of Colombia and Venezuela and Guadeloupe 

 on St. Thomas and St. Croix. Recorded from Cuba. 



Acanthocereus pentagonus. 



Introduced 



