192 



THE CACTACEAE. 



14. Hylocereus trigonus (Haworth) Safford, Ann. Rep. Smiths. Inst. 1908: 556. 1909. 



"iCactus triangularis foliaceus Jacquin, Stirp. Amer. 152. 1763. 

 Cereus trigonus Haworth, Syn. PI. Succ. 181. 1812. 

 Cereus venditus Paulsen, Journ. Bot. 56: 235. 1918. 



Stems slender, 2 to 3 cm. broad, clambering over bushes or rocks, sometimes 10 meters long, 

 deep green; joints 3-angled, the margin of the ribs not horny, strongly undulate, the areoles borne 

 on the tops of the undulations; spines usually 8, 4 to 7 mm. long, stiff, at first greenish, soon dark 

 brown; accessory spines or bristles usually 2; perianth large; ovary bearing large foliaceous scales; 

 fruit oblong or oblong-obovoid, red, 10 cm. long, becoming nearly smooth. 



Type locality: Not cited. 



Distribution: Hispaniola, Porto 

 Rico, Vieques, Culebra, St. Jan, St. 

 Thomas, Tortola, Virgin Gorda, and 

 St. Croix. Recorded by Boldingh (Fl. 

 Ned. West Ind. 297) from St. Eus- 

 tatius, Saba, and St. Martin. 



This species, although known to 

 Plumier and illustrated by Burmann 

 (1 750-1 760), was not taken up as a 

 species until 181 2, when it was de- 

 scribed by Haworth. In 1803 Haworth 

 had described it as a variety of Cactus 

 triqueter (Misc. Nat. 189), but had 

 said it was twice the size. Cereus 

 venditus Paulsen is based upon the 

 juvenile form of this species from a 

 plant collected on the Island of St. Jan. 



Illustrations: Safford, Ann. Rep. 

 Smiths. Inst. 1908: pi. 12. Plumier, 

 PL Amer. ed. Burmann, pi. 200, f. 2, 

 as Cactus etc. ; Contr. U. S. Nat. Herb. 



8: pi. 25, as Cereus sp. ;? Jacquin, Stirp. Amer. pi. 181, f. 65, as Cactus triangularis foliaceus; 

 Loudon, Encycl. PL f. 6872, as Cactus trigonus. 



Plate xxxvi, figure 1, represents a fruiting joint of a Porto Rican plant in the collection 

 of the New York Botanical Garden. Figure 268 is from a photograph taken by F. F. L-utz 

 near Arecibo, Porto Rico. 



15. Hylocereus triangularis (Linnaeus) Britton and Rose, Contr. U. S. Nat. Herb. 13: 429. 1909. 



Cactus triangularis Linnaeus, Sp. PI. 468. 1753. 



Cereus compressus Miller, Gard. Diet. ed. 8. No. 10. 1768. 



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



High-clambering or creeping vines, sharply 3-angled, 3 to 4 cm. broad, giving off numerous 

 long aerial roots ; margin not horny, nearly straight or slightly elevated at the areoles ; areoles about 

 2 cm. apart; principal spines 6 to 8, acicular, but with swollen bases; flowers 20 cm. long or more; 

 outer perianth-segments linear-lanceolate, acuminate, 6 to 8 cm. long, longer than the inner seg- 

 ments; inner perianth-segments white, oblong; scales on the ovary and flower-tube oblong, green, 

 2 to 5 cm. long; fruit red. 



Type locality: Jamaica. 



Distribution: Very common on rocks and trees along the coast of Jamaica. 



Plants of H. triangularis were collected by John F. Cowell in Panama, probably not 

 native there, however. 



Cereus triangularis pictus De Candolle (Prodr. 3 : 468) is said to have yellow or yellow 

 and green joints, with spines often setiform, not rigid. 



Fig. 268. — Hylocereus trigonus. 



