200 THE CACTAC3A3. 



This species has long passed as Cereus kunthianus and is the plant described by Schu- 

 mann under that name. 



Figure 275 is from a photograph of a branch of a plant collected by 0. F. Cook at 

 Panzos, Guatemala, in 1907. 



5. Selenicereus donkelaarii (Salm-Dyck). 



Cereus donkelaarii* Salm-Dyck, Allg. Gartenz. 13: 355. 1845. 



Stems elongated, creeping or ascending, 8 meters long or more, slender, about 1 cm. thick; ribs 

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

 appressed; central spine 1 or several, 1 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 1 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 E- 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. 



Cereus pteranthus Link and Otto, Allg. Gartenz. 2: 209. 1834. 



Cereus nycticallus] Link in A. Dietrich, Verh. Ver. Beford. Gartenb. 10: 372. 1834. 



Cereus brevispinulus Salm-Dyck, Hort. Dyck. 339. 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 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-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 book as Cereus donkelarii. It is also written Cereus donkelaeri. 



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



