STANDLEY TEEES AND SHRUBS OF MEXICO. 915 



Mexico, but known only from cultivated plants or from plants escaped from 

 gardens. 



Stems stout, often 3 to 5 cm. in diameter, bluish green to purple, strongly 

 4 to 6-angled ; ribs of young branches sometimes 2 to 3 mm. high ; spines 1 to 4, 



1 to 3 mm. long, dark, conic ; flowers 25 to 30 cm. long, very fragrant, the tube 

 and throat 13 cm. long, swollen above, 5 cm. in diameter; outer perianth seg- 

 ments linear, 12 cm. long; inner perianth segments white, spatulate-oblong, -3 

 to 4 cm. broad above, acuminate ; tube proper about 2 cm. long, yellow within ; 

 ovary covered with long white silky hairs and bristles, 10 to 12 mm. long; 

 fruit globular, red, 6 to 7 cm. in diameter. 



5. Selenicereus boeckmannii (Otto) Britt. & Rose, Contr. U. S. Nat. Herb, 



13: 429. 1909. 



Cereus boeckmannii Otto; Salni-Dyck, Cact. Hort. Dyck. 1849. 217. 1850. 



Cereiis irradians Lem. Illustr. Hort. Lem. 11: Misc. 74. 1864. 



Cereus vaupelii Weing. Monatsschr. Kakateenk. 22: 106. 1912. 



Eastern Mexico. Cuba and Hispaniola. 



Stems light green, 1 to 2 cm. in diameter, strongly angled ; ribs 3 to 8, 

 slightly if at all undulating ; areoles at first brownish but white in age ; spines 

 and hairs in the areoles at first purplish, the spines 3 to 6, becoming yellowish, 



2 mm. long or less; flowers not fragrant, 24 to 39 cm. long; outer perianth 

 segments and scales linear, brownish ; inner perianth segments ob.lanceolate, 

 10 cm. long by 3 cm. broad at widest place, pure white; tube and throat 14 

 cm. long, bearing scattered short linear acute reddish scales, their axils bear- 

 ing long brown silky hairs and brown bristles; ovary strongly tuberculate; 

 fruit globular, 5 to 6 cm. in diameter. 



6. Selenicereus hamatus (Scheidw.) Britt. & Rose, Contr. U. S. Nat. Herb. 



12: 203. 1909. 



Cereus hamatus Scheidw. Allg. Gartenz. 5: 371. 1837. 



Cereus rostroius Lem. Cact. Aliq. Nov. 29. 1838. 



Southern and eastern Mexico. 



Stem bright green, long and clambering, the branches strongly 4-angled, 

 rarely 3-angled, about 1.5 cm. thick; areoles with spines and black wool, re- 

 mote, at the upper edges of knobby projections, these often forming obtuse 

 deflexed spurs about 1 cm. long; spines on juvenile plants bristle-like, white, on 

 old branches fewer, stouter, brown or black ; flower 20 to 25 cm. long ; upper 

 scales dark green, tinged with red; outer perianth segments pale green, nar- 

 row, about 8 cm. long ; inner perianth segments broad, white ; flower tube 10 

 cm. long, 22 mm. in diameter, its areoles long-hairy. 



7. Selenicereus vagans (K. Brandeg.) Britt. & Rose, Cactaceae 2: 205. 1920. 

 Cereus vagans K. Brandeg. Zoe 5: 191. 1904. 



Cereus longicaudatus Weber; Goss. Bull. Mus. Hist. Nat. 10: 384. 1904. 



Western coast of Mexico ; type from Mazatlan, Sinaloa. 



Stems creeping over rocks, often forming large clumps, more or less rooting, 

 1 to 1.5 cm. in diameter ; ribs about 10, low ; areoles 1 to 1.5 cm. apart ; spines 

 acicular, numerous, less than 1 cm. long, brownish yellow; flower 15 cm. long; 

 tube, including throat, about 9 cm. long, slightly curved, brownish, with small 

 scattered scales bearing clusters of 5 to 8 acicular spines in their axils ; throat 

 narrow, 5 cm. long ; outer perianth segments linear, brownish to greenish 

 white, 6 cm. long; inner perianth segments white, oblanceolate, 6 cm. long, 

 with short acuminate tips, the margins undulate or toothed, especially above; 

 ovary covered with acicular spines. 



