2OO 



THE CACTACEAE. 



Tliis species has long passed as CCITHS kitntliianus and is the plant described by Schu- 

 mann under that name. 



l-'i^urc 275 is from a photograph of a branch of a plant collected by O. F. Cook at 

 1'anxos, Guatemala, in 1907. 



5. Selenicereus donkelaarii (Salm-Dyck). 



Ci-n-tis donkelaarii* Salm-Dyck, Allg. Gartenz. 13:355. 1845. 



Stems elongated, creeping or ascending, 8 meters long or more, slender, about i cm. thick; ribs 

 g or 10, obtuse, often indistinct; spines in clusters of 10 to 15, the radials 3 to 4 mm. long, setaceous, 

 appressed; central spine i or several, i to 2 mm. long; flowers 18 cm. long, the slender tube 6 to 

 7 cm. long; outer perianth-segments reddish, linear; inner perianth-segments white, entire, 6 to 8 

 cm. long, about i cm. wide, acuminate; stamens and style nearly white above, greenish below; fruit 

 unknown. 



Type locality: Not cited. 

 Distribution: Yucatan, Mexico. 



FIG. 276. Selenicereus donkelaarii. 



This species has long been known only from cultivated plants. Schumann reports it 

 as from Brazil but this we are now disposed to question since it has recently been dis- 

 covered by Dr. George Gaumer in Yucatan growing in dense forests, and we now have 

 living specimens from his collections. We now find that Major H. A. Goldman collected it 

 some years ago in Yucatan but it was not recognized at that time. Goldman's plant grows 

 in dense patches on Cantay Island, collected April 22, 1901 (No. 661). 



Figure 276 represents a sterile branch of the plant as grown in the collection of the 

 United States Department of Agriculture. 



6. Selenicereus pteranthus (Link and Otto) Britton and Rose, Contr. U. S. Nat. Herb. 12 : 431. 1909. 



Crreus ptcrantlius Link and Otto, Allg. Gartenz. 2: 209. 1834. 

 Cereus nyrticalliis^ Link in A. Dietrich, Verb. Ver. Beford. Gartenb. 10: 372. 

 brevispinulus Salm-Dyck, Hort. Dyck. 339. 1834. 



1834. 



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 i to 4, i 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-segments linear, 12 cm. long; inner perianth-segments white, spatulate-oblong, 3 

 to 4 cm. broad above, acuminate; filaments numerous, greenish to cream-colored, the upper row 

 reaching forward, upturned near the tip, 6 cm. long; lower stamens elongated, unequal, 8 to 12 cm. 



*The species was originally spelled in the Allgemeine Gartenzeitung Cereus donkelaarii but was indexed in the 

 same lunik as i'l-teii* tlimkrlarii. It is also written Cereus donkelafri. 



tAlthough the usual spelling of this name is with one 1, it was originally spelled by Link as it is here. 



