REVISION OF THE GENUS CEREUS MILL. 67 



The flowers of C. stellatus Pfeiff. open fully only for 

 a very short time. I have seen them open on a dark morn- 

 ing for about two hours, but otherwise failed to observe 

 them expanded, and for a long time I believed them to be 

 cleistogamous. Soon after flowering they fell off, produc- 



ing no fruit. The 



much 



nectar, so much that it finally reaches the stamens or 

 even fills the whole flower. 



Cereus Aragoni Web., from western Costa Rica, seems 

 also to belong to this subgenus according to the descrip- 

 tion of the flower given by Weber.* This plant is now 

 cultivated in some gardens in Europe, and I am informed 

 by Mr. Weingart, of Nauendorf, that it seems closely allied 

 to C . prainosus Otto and C. eburneus Salm. If this is true, 

 these two species also may probably belong here. C 

 resupinatus Salm has also been united by Schumann with 

 G. eburneus, but this is certainly a mistake. Mr. Wein- 

 gart, of Nauendorf, possesses this plant, which agrees 

 exactly with the figure (no. 93) in Forster-Riimpler. 



It is not clear from the description whether JPilocereus 

 Tetetzo Web. (K. Sch. 1. c. 175) is also a Stenocereus. 



s 



VIII. EULYCHNIA Phil. Flor. Atac. 23.^?. 11a. (1861). 



Flowers campanulate with a short and broad tube ; ovary globose 

 or turbiniform, like the tube with numerous deltoid or acute scales, 

 often densely covered with wool, setulose hairs or bristles; sepaloid and 

 petaloid perianth leaves small, reddish or white; filaments numerous, 

 little shorter; styles deeply divided Into numerous stigmata. Fruit 

 globose, more or less woolly, setuliferons or prickly. — Plate 4,f. 1. 



Frutescent or columnar species from the Andes of South 



America. 



Philippi has given no clear definition of his genus. He 

 founded it upon the very setuliferous flower of C brevi- 

 JlorusK. Sch. and afterwards added to it two other species 



* Les Caches de Costa Rica. Bull. Mus. d'Hist. Nat. Paris. No. VI. 

 455. (1902). 



